I'm still using Windows 7 in my home computer, for gaming no less, and only recently did some games come out that don't support it and the only significant push to upgrade is the upcoming (end of year) end of Steam support for it, which is just going to make me use my Linux partition for games more.

Roughly only in the last 2 years have I started to have any inconveniences from having Windows 7 - basically the latest KiKad, for circuit design, doesn't support it, so I kept using the previous version which has very rarelly has forced me to go find component and footpads which I would otherwise have already in the latest one.

The point being that if Windows 7 only started to get incovenient to use (both for gaming and professionally) well beyond not just Windows 8 having been launched but even Windows 10 having been launched, it's reasonable to expect that Windows 10 will still be fine for use for many years.