I don't think there's any market. The only people who buy macs are people that have no intention of playing videogames on that system.

I personally transitioned from Windows -> Linux -> MacOS, and each switch correlated exactly with how much I was playing videogames at that time. I don't play games anymore which is why I'm perfectly content using a mac. If I wanted to play games again I would go back to linux, or all the way back to windows.