Without going into a flame war, I made my first game (open source engine) on Linux, 100%. Even Windows binaries were cross compiled. After that I switched to Windows and never looked back. Now, I’ve heard “Linux is the future of gaming” since 2008. Nothing has changed since then (well, maybe Nvidia got better video drivers than the other two vendors and Linux now looks sort of like Windows). Linux has been a small tiny market for the past 8 years. It’s vocal, but it brings very little revenue. There are a peak of it in 2010-2013 where it was quite popular and got a lot of press coverage, but since then enthusiasm has died down and it’s no longer the thing.
Yes, Windows 10 isn’t as good as Windows 7, but I am certain in ~2 years Windows 10 will be as mainstream as Win 7 was/is (after MS gets it’s head out of it’s bottom and starts listening to users; or if Ubuntu does the same and MS will feel threatened).