so, what would happen if some third party started offering updates and maintenance for older operating systems?
Corporations would be happy, but home users often don't understand patching. Let alone third party patching. MS controls the built in patching mechanism, and it's become much more functional since Win 7.
Win 8 is a corporate no-go. It's probably fine for consumers. Don't know, don't care, not my market segment. For enterprises? Yea. It's like Vista, but less usable. It allegedly has some awesome enterprise features. Which no enterprise will use because they're not drunk or high enough to use Win 8. Allegedly 8.1 would address these concerns. Instead, 8.1 was a barely disguised "No, **** you". Allegedly, 8.2 will address these concerns. I give it 50/50 that it's another "No, **** you" to enterprises vs a pseudo Win 7 ish desktop. Either way, Win 9 will look like Win XP or Win 7, with a changed start menu that looks goofy and stupid but works well enough.
Win 8 bet that everyone and everything will have touchscreens. They lost that bet. They bet everyone WANTS a unified OS between their Xbox, their desktops, their tablets, their phones and their servers. They must have been sniffing various neurologically damaging solvents at the time, but that was their bet. They lost that bet.
So, Win 8, Win 8.1 and Server 2012 are dead on arrival. Allegedly Win 8.2 and Server 2012 R2 will magically fix these problems. Solution is easy, obvious and cheap. Slap on an optional (that corporations can make mandatory via group policy) Win 7 desktop. Ideally, Win 7 desktop with all the eyecandy turned off. I'd hand Microsoft buckets of cash overnight for such a thing.