Funny. About 50% of my steam games do not run on linux and while many can be installed they usually come with all kinds of glitches and issues. The harsh reality is that until linux requires absolutely zero extra lift for end users, windows will still be the default for the overwhelming majority. God i hate windows but they are the only company who gives a damn about gaming anymore.
There are a lot of people that are used to tweaking games on Windows, too, I used to be one of them. Lots of people mod their games and have to run them differently to do so or have to shim them in some way to make them work, lots of people search to find answers to problems they are having. Getting up to date graphics drivers used to be a pain in Windows (haven't had to try for many years), it's part of system updates in Linux for me (even running NVIDIA cards). If anything, getting a game to work that has issues on Windows was harder than getting a game to work on Linux that is having issues thanks to protondb.com, at least for me.
So I think there are a lot of people that could just hop over if they wanted to, trading one kind of tech-related problem solving for another kind.