I think a large reason why many game devs don’t dev on linux is tooling support, not the speed of the runtime. idk if Unity and Unreal editors run on Linux but they do make it simpler to target linux or mac. Ancedotally, however, most Unity devs I see are either on Windows or Macbooks, not Linux.
Personally I’m a fan of DirectX and all the tools that come with it. Vulkan is a comparable API (though more verbose than DX11) and the tooling support for it is very 3rd party. I could switch to Linux for literally anything other than game dev because I’m just too into DirectX right now