Most games. Most of the time. You make it sound like there's only a small subsection of games that can be played on Linux when that hasn't been true for some time now.

There definitely still exist games that have issues running on Linux, but they are few and far between now.

In my experience these days, across several dozen games in my Steam library (admittedly largely omitting competitive multiplayer games other than CS), it has been most games, most of the time, on a basic Ubuntu install on hardware I chose mostly without checking for Linux compatibility. If you want to play video games without paying Microsoft for user-hostile systems, Linux has definitely become a genuine option in recent years.

I have a Windows 10 install on my machine that I have been thrilled to discover I’ve only needed a handful of times in three years (mostly to disable the rainbow vomit RGB that Linux doesn’t recognize).