I've avoided the T2 issues with pre-T2 systems (except for my wife's Mac Mini which has been flawless). I've seen complaints about it here and there - but, if you use Time Machine, can't you just restore to another system? That's my backup plan - if I lose a machine, then I can just buy another and restore from Time Machine. Can't you do the same thing with the newer Macs as well?
I have two Pre-T2 systems so I could also just pull off the files from the backup of the other system. I do agree that it's a good idea to have two systems if your livelyhood depends on it, and, especially if the systems are over five years old.
I have a Mac mini 2018 (with the T2 Security Chip) and it is easy to make bootable clones of the system drive to an external SSD using Carbon Copy Cloner. The presence of the T2 chip does not impede this.
Yes, you can restore a new machine from a Time Machine backup. That's what it was designed to do, T2 chip notwithstanding.
I can boot an alternate operating system from an external drive on my Mac mini 2018. For the past 11 months, I have evaluated Catalina on an external drive and yet kept my internal boot drive on Mojave. At this point, it is a given that I will end up skipping Catalina and will move to Big Sur directly but not before creating a bootable clone of my Mojave system which I will keep around for as long as I own this machine.
Again, the T2 Security Chip doesn't affect any of these scenarios. I don't really understand why some people are so averse to the T2 Security Chip.
And guess what? Once Apple Silicon is here, security will be even more tightly integrated on Macs. The T2 Security Chip was a stop-gap measure while Apple was using Intel CPUs and occasionally AMD GPUs.
Returning to the original topic, I am quite satisfied with my budget Acer Swift 3. I bought one with the 10th generation Intel CPU and it has Thunderbolt 3. This allows me to plug it into my Sonnet eGFX Breakaway Box 650 + Sapphire Pulse Radeon RX 580 combo should I want better 3D graphics performance.
Today I rarely do that since I have a much more capable custom built Windows gaming PC (Nvidia GeForce RTX 2070 SUPER). However the Acer Swift 3 remains a very reasonable $750 stand-in for the MacBook Air 2019 (at twice the price) that it replaced.
Of course it runs Windows 10 but it turns out that for my particular usage case having an Apple operating system on a notebook computer is pretty unimportant.
Either this site or AppleInsider had a recent notebook customer satisfaction survey at Apple unsurprisingly ranked at the top. The big takeaway was that most of the PC manufacturers were in a big field about one or two percent points from another. While Acer was ranked near the top of the PC field, it was just one point higher than than the pack, a statistically insignificant amount.
These customer satisfaction surveys don't assess hardware durability. In my own experience, Apple hardware lasts longer than their competitors. However there are vast differences in software support.
Apple only provides macOS security updates for the previous two operating systems, right now Mojave and High Sierra. Once Big Sur is released, High Sierra will stop receiving security updates and Catalina will start receiving them.
By contrast, Microsoft is spectacular at providing current Windows compatibility with some very old hardware. Apple eventually stops supporting old hardware. My Mac mini 2010 ended at Mojave (which it did not run well); I went back to Sierra but it was clear that the system no longer could do the modern tasks I needed from it.
With mobile devices, the picture is very different. Apple provides iOS/iPad OS/etc. support for many generations of devices. However updates to Android devices are infrequent and rare, most of them targeted at the flagship premium models. For most Android devices, they probably won't see any new OS-based features
EVER.