Yeah but Windows isn't inherently better at gaming because it gives something the other platforms don't (DirectX12 can easily be replaced with Vulkan)
It's a matter of the market choosing it's main Target and sticking to that
I can run the original Quake and DOOM on Windows 10 without any problems. A friend of mine like playing GTA 3, it didn't work properly with Windows 8.1. In an update this incompatibility (I forget the exact reason why) was fixed.
That just doesn't really happen with Linux.
Intel drivers have been historically always much better in DirectX as in OpenGL, where they even used to lie about their available GL capabilities.
AMD, since they dropped my card from their FOSS drivers, I don't have much fate on their FOSS love.