> I can agree audio is now OK, but everything else is as sketchy as ever was.
I politely disagree. It has its warts, but most of the OP's complaints were true--10-12 years ago. Now, not so much, and it's not anecdotal either. Let's go back over it by point:
- Hardware video acceleration? Works on most hardware ("most" in this instance refers primarily to vendor). NVIDIA cards are almost always guaranteed to work well, provided there's driver support. This is usually the case except for brand new cards.
- xorg.conf edits required? Nope. Maybe for exceedingly special cases. It's rare now unless you're using a card that's not well supported (see above).
- xserver crashes? Almost unheard of outside hardware problems or driver-related issues. Usually a PEBKAC-instigated fault.
- UTF-8? No point talking about this...
- Random USB devices? Depends on the device. Same for Windows, really.
- Manual invocation of `startx` required? Uncommon. Most distributions ship with login managers that work quite well. If you're using a rolling release, you'll probably have to do this infrequently if an update broke something (but then, you should be expecting that with a rolling release anyway; if not, then you shouldn't be using rolling releases).
> It was _the software ACPI support that broke,_ not hardware
I apologize. I misread your original comment due to misleading verb ordering, and the fact that I'm a horrible, horrible person who has an awful habit of skimming comments.
Generally this shouldn't be the case and is certainly the fault of the kernel. However, 4.0 was released on April 12, 2015 and there have been a number of improvements since, including with ACPI. I would encourage you to try a newer kernel. Preferably something around the 4.7-4.8 vintage. (Or lack thereof.)
It's also plausible your issue was cased by module renaming/removal. My memory is hazy on this part, but I recall support for some hardware being rolled up into a single module, requiring some manual intervention. Unfortunately, the actual working solution can be hit or miss with some hardware (what motherboard are you using?). I've had ACPI work fine on ancient boards from circa 2000ish or earlier (tested recently for my own amusement) but fail completely on recent laptops (2014-2015) out of the box. I'd suggest starting here [1], although this guide may or may not be useful as it's for Arch. It'll at least give you a good start.
ACPI is one of Linux's primary warts, but it depends on your hardware selection. Is it a problem? Absolutely. But I'd also point out that Microsoft used to publish hardware compatibility guides for NT and its various successors. :)
Common hardware will go a long way to improving your experience with Linux, but it's no replacement for researching one's selection. Linux may be condemned to a hobbyist's operating system (on the desktop, at least), but some of us do use it everyday with no ill effects!
[1] https://wiki.archlinux.org/index.php/ACPI_modules