You are right that Windows was a bad choice of platform for so many reasons, but usually the decision is based on what is cheap & practical now, with the presumption that product development and support will continue so upgrades to newer hardware/OS are thus managed.
In practice companies fail, get bought over, or otherwise decide to orphan products so support stops but lots of users have business-critical stuff that is no longer upgradable when the OS, like Windows, drops aspects of backwards-compatibility (often for other good reasons, like security).
Sadly short of an open source system, you are stuck making the best of what you have, not what you wanted.
More recent MS OS with product activation checks are even worse and should never be used. But they will, because some green programmer only knows that way and all problems look like nails...
But retuning to one of your gripes, that of PC hardware, what other computer platform has been more-or-less supported for 20 years? It is far from ideal, but a longer supported choice is hard to find.