This is probably as important a factor as any. We* are inclined to actually take a bit of care of our computers. We care that they run right. We care that they're secure. As such, our Windows machines typically don't have all the sorts of problems that average users pan Windows for. Microsoft could make this easier for us, to be sure, but all that most people see - and therefore what most people talk about - is the UI, so they constantly fiddle with that rather than fixing the things that make us angry.
So, we get cross at Win10 for not fixing the things we care about, and for making the things we don't care about, from our perspective, worse. Everyone else gets cross because things are different and anything different is something to learn and they didn't want to learn anything in the first place.
* Reg readers, "technical people" in general