So, let's have a bit of fun here, since it seems like heavier portions of the discussion have started to rule it.
Windows 7 is Vista with the fat cut, and properly optimized. Windows 8.1 is windows 8 with some of the more...interesting...decisions rolled back. Both 8.1 and 7 are very much respectable OS decisions, depending upon usage. Vista and 8 are functionally mistakes that have been rightly forgotten (8.1 can be argued to be a service pack, but in my experience it changed about as much as 7 did from Vista).
How long before we see a 10.1 release, that is functionally rolling back some of the more quirky changes? I know MS plans for 10 to be a rolling OS that could functionally be subscribed to, but who really thinks that plan is going to be followed? Two questions, I wonder how many answers are possible?
Are you being sarcastic?
If not, that's the best joke I've heard all day. Between video card drivers being insanely pragmatic for certain configurations, and the dozens of companies which produce interacting hardware (Realtek drivers anyone?), MS can't really expect the manufacturers to update everything. Not even considering crap like the recent updates which borked tons of USB devices using non-authentic chips, how do you expect everyone to write entirely stable and universal drivers for their stuff?