There are some oddities here that someone older (like me LOL!!) finds glaring because "the more things change, the more they stay the same" and "everything old is new again".
First, right out of the box, all our cMPs were different (for instance, they did not have a camera out of the box and did not work with the external iSight camera before that low res camera vanished into history --((AFAIK))) than the iMacs and whatever laptop the reader would like; it was, even back to the first PowerMacs, as if Jobs had designed the toasters and Woz had designed a refrigerator. You can customize a refrigerator a great deal and it is great at managing temperature; it even has two "processors!" In a very real sense, all of us cMP people are different because we want to know things about --probably, almost anything-- something that probably exists far beyond most people's interests or concerns. This is not some arrogant pronouncement, a lifetime is finite and some people, just as they do with cars, medical, or dental care, want Jobs' "just works" toaster, as long as it works. For Apple, the user experience is part of "the whole widget" and their "obsolete" is just "suboptimal user experience" rather than "well, if you still want to use that 'antique' you can turn it into a printer server or a firewall" found elsewhere. A cluster of water cooled G5s can make mincemeat of mountains of data, it just cannot use Big Sur; on the other hand, people talking about clusters and data were probably "think different" before someone made a poster.
Hate the trashcan Mac Pro? I learned BASIC on a Commodore PET and the first machine I owned was a VIC-20. Back then, "upgrade" meant something like "plug it in" without the benefit of even the hope of a hub --a switch, then a heavy steel box with a large rheostat and enough resistors and capacitors to open your own RadioShack, is NOT a hub. In practice, this meant that a huge desk was needed to stretch out the wires (for longevity and cleaning*) from some peripheral to a switch and thence to the actual computer. Outgrew your VIC-20? Here's a C-64, none of the peripherals will work but at least the switches will! You could, daisy chain the floppy drives but it slowed the data transfer and the plastic box held on to a lot of heat; as heavy as they were, there had to be a fair amount of metal in there along with whatever made them "smart peripherals" --the intent was to free the 6502 in the machine to do work while the data came and went. ** The year I started drooling over Lisa (1983), the desk spanned somewhere around 12 feet! I had homework to do and I am a night owl so I made a sound "suppression" enclosure for a dot matrix printer that without the enclosure could give a line printer a run for its money; 14 feet of desk and space for boxes of tractor feed paper and little by little, every creature comfort left the room and THEN, the bookcases came. WordStar was still in the future (for us anyway) and there were already TWO! Just for the computer books and an issue or two of Computer Shopper.
I am not trying to say something like "when I was your age... uphill, both ways... in 10 feet of snow", I am just trying to illustrate --vividly, I hope-- a past before NAS and Thunderbolt and wall mounted monitors that can move to ergonomic perfection. I believe that the idea is that for most people, the weight of their OMG laptop matters and the idea that should they forget it somewhere, killing it is a phone call --at worst-- away is a major selling point. When an AX router can handle the NAS (or two!) and a laser printer and it can all be found in a closet in the basement, why bother with anything other than a beanbag and some Apple Music over any number of Bluetooth speakers? My mom yelled, parents today, FaceTime when it is time to eat --"Nag different?". The price? About every three years, take the old one in and trade it in for another WOW! machine; UNIX? What is that? Data? Math? Normalization? Python vs. Java? XML? Pantone? Now you are just making stuff up!
The thing is, when time comes to trade something in, all the other crap still works because the wifi is backwards compatible (what default password?) and no one has to worry about WinTel gamer vs Mac creative or compatibility. I wish I could say that I have a nixie watch and an HP-48GX but I'd wager that few here have either and some might need an explanation for either or both; however, somewhere near you... "and we are calling it iPhone!" I hate it but Jobs version of the world would seem to be "right" for most.
Hang in there... just a bit longer...
I have been digging around the windows registry since NT4 and 95 and I know just enough to get in trouble there as well but between that and slipstreaming and cut this and that out, I worked with a version of windows XP for years on a pentium III. It could only run office --no macros--, a portable browser, and a registry editor but it could not catch a cold in a smallpox ward. I did something similar for windows 7 for a friend with one of those netbooks and he would have been better off with NetBSD or Debian. By the time that anemic Atom did anything worth doing, windows had turned off so much that portable software did a better job for almost anything; however, before I stripped out all sorts of junk, anemic or not, it could not only be sick, it could be the cause of sickness in others. Microsoft is no better --and often worse-- at supporting software than Apple; it is more important for them to sell you a new version than it is for Apple, they don't have an actual widget to sell you! Then there's the WinTel modems that are interconnected to RJ-45 and phone (whew! that's a long time ago eh? LOL!!) with which, Microsoft guaranteed that I will look for UNIX compatibility (today, that means look at a Mac first, Linux laptops have --in my experience-- issues with wifi and bluetooth radios and probably something or other else unless Red Hat Enterprise is your distro of choice) first because something that can run iLumos (the open source version of Oracle's System V R.4 based UNIX) or OpenBSD will almost certainly do fine with any Linux.
Unless you need to write code for an AS/400 or some other prehistoric dinosaur, Windows is not versatile, it is poorly planned and poorly executed. Please, allow me to explain: yes, there are a million ways of doing anything, unfortunately, that is because no one actually thought about the need to do whatever it is you are doing, anyone that has driven the beltways around Atlanta knows exactly what that is like. Eventually, you get used to doing something a certain way (it was so easy to use the control panel that I forgot what I had learned as a kid beyond 'learn the stuff they cant change' --forgot that as well--, I forgot the cryptic dos names) and everything is fine until they change a small portion of your path (something like "Road Closed, Bridge Out") and the cussing and swearing and the headaches come back. The truest versatility is the considered option: when you install windows, no one asks if you want the internet explorer based file system utility or if you want explorer.exe to be your shell. Indeed, no one asks if you want the gigantic footprint of windows 10 as opposed to "give me the barest GUI and the footprint of the micro install of windows server". You are not even asked if you want every port in the universe open by default or not. Insanely, the option that was available in windows 2000 to install an actual UNIX subsystem (a Sys V R 4 derivative no less) is not available, a toy version of linux is shoved along side PowerShell and a kindaDOS for nostalgia. The versatility of windows is a mirage enhanced by gaming and VR toys. I say that because DirectX will not improve the word processing or spreadsheet image but when you are tired, it will improve the heck out of the most demanding game. This is not an impossible dream, all these things are possible in the current edition of Windows Server --hopefully, sans wannabe Linux. Microsoft just doesn't know whether it is coming or going, ask Nokia or SCO or let Steve Balmer tell you about the iPhone... I wonder who will be the next "Steve Balmer" when it becomes clear that Windows2000 had the right stuff and 10 and Linux is just another "Zune".
Apple will not give me everything I want --not a single option-- but I do have Posix/SUS (lose that and "nothin' but the taillights") and everything is closed by default and security is so tight that the most dangerous thing to a Mac is the operator. They will not support cMPs with Big Sur but it will install and they will talk about it for free without too much trouble --if you are using one of their services when you have the problem, it will be like the first day! Microsoft wants to sell me Office (first developed for Macs) while Apple gives me something that installs locally for free. Microsoft would have to make such a game changer of a citation manager to sell me something that they would rather lose most of the academic market than do something so obvious. Apple has not treated anyone "creative" decently in a long time *** but, at least, my citation database (I lost everything I had on Mendeley which I used to recommend) will be safe on iCloud. At least, the defaults system does Boolean algebra...
Why all that? Planned obsolescence is probably not a problem for anyone here. The very fact that you ARE here means that you are able to ask for help when you don't know and help others when you do --surprisingly rare qualities. I started with my cMP with the knowledge that I would have to learn enough UNIX to survive the inevitable moment when I would not have enough money available to get an equivalent jump in Mac Pro. Paper bag calculations suggest that I would need somewhere around 10k for replacement capability (still no camera or serious audio) that would not include equivalent upgradability. On the other hand, Dragonfly BSD would seem to be all about optimizing SMP performance and OpenBSD provides security that is good enough for a bank; I do not yet know which way I will go but I have a few years to decide, Big Sur will install if the support check is inactivated and security updates (did I get this right?) will install even if nothing else will?
There is far more UNIX to learn than I ever thought possible --where on a PDP-11 could they have put all of these commands and switches!-- but I do not expect to have to channel Dennis Richey daily, there are people here and in the UNIX forum that can help if I get stuck. The fact is that when Apple stops supporting cMPs (apparently, now?) my machine will not suddenly turn into a victrola and neither will yours; stay away from windows, friends don't let friends use things that need their config.sys or autoexec.bat checked, lack pipes, or are so buggy that people turn off the "features" that caused them to buy the machine in the first place. Since the last time I was doing something inside my cMP, people at MacRumors have found ways to drastically increase the ram, instal 802.11ac, and add thunderbolt 3 and handoff and continuity WILL work (as opposed to "y'all watch this!") These machines are serious beasts and will blow people away (what windows machine that is as old as my cMP can handle 160gb of ram?) long after Apple realizes that with a little effort they could have kept customers for their music and storage services happy and telling everyone about The Apple Experience.****
Please forgive my chattiness, thank you for reading this far.
* The actual wires were generally no thicker than those in a thiner wire, the thickness was RF insulation and even then, it just wasn't that great; however, a coiled over wire that hung from the desk was a recipe for disaster and I never bought a cable back then for less than 20$.
**I am not comparing anything to the Apple of IIe times because anyone that had a machine that could have cards added to a riser such that they could not close the lid simply did not have a comparable experience.
*** Ritchey, Thompson, and Kerrigan could not get AT&T to buy them a new Mac Pro today even after the ACM award! The world is so screwed up that someone would probably offer them three iMac Pros instead.
****If anyone at Apple reads this: Sell us a service that will keep us on MacOS by providing security and functionality maintenance.