Perhaps, because win7 is known for being "the last good windows" with some privacy. It may or may not be true, but a lot of people are adamant about not using linux while also trying to maintain privacy, hence they use win7. I imagine such users would probably use a browser like firefox.
Nah there was definitely some kind of fundamental qualitative change from 7 to 8/10. I dont think the post-7 versions of windows will ever be loved like 7
