Not necessarily. You'd be surprised. I just picked up a Synology DS212j for $219.99. That, plus HDDs, you can get one up and running for less than $400. Now, there is supposedly a huge shortage of HDDs in the world right now, so prices are through the roof, but you can normally pick up a good 1TB HDD for about $60. That means, under normal world circumstances, you can get one up and running for less than $350...and you'll never have to worry about iCloud/Dropbox/new storage of the month problems and prices. Oh, yeah, and it just works.
I hear you though. You'd think asking Apple to just store your documents for easy retrieval off the web would be a small task. But, no. For some reason that tried to be all cute and outsmart everyone by restricting such an easy, even-your-grandma-can-do-it feature.
Yeah, I don't know why they didn't just delay iCloud until it was all worked out.
As for the NAS stuff, there's also the fact that the reason I switched to Mac was to avoid building things, finding the right drivers, figuring stuff out etc. I looked up NAS enclosures the other day and there's tons of opinion on which ones are better or more reliable or support certain RAID drivers, bla bla bla. I refuse to deal with any nonsense like that anymore. If I'm gonna do all that then I might as well just go back to Windows. If Apple made an iNAS Express (lol) that I could just plug in to the router and be done with it that's one thing, but I don't want to deal with setting up my raid array and worrying about my backups and setting up the ports and all the other unforeseen crap that would arise from putting together a piece of hardware like that.