(The “Windows” slices of the pies are entirely made up by Baldur’s Gate 3, which also runs well over Linux)
Yeah, that’s not the whole story
Enabling Linux support does inherently allow more attack vectors that need to be secured that don’t need to be if it’s windows only. Linux works against these kinds of anticheats, as they’re working to get the most information out of the system as possible to prevent 3rd party programs from being run. This is a major design consideration in Linux not present in windows, so there is considerable extra work that has to be done, on top of already being much less effective on Linux than they are on windows.