If Microsoft has a monopoly on gaming it’s not because they’ve made an effort to build one. It’s just that MacOS and Linux have never been actual competition. Linux because the user base was so small that making games for it was a big financial risk. SteamOS devices could change this but I doubt it.

And Apple just wont put the effort in for some reason. I’m sure they could make a huge dent on the market, as every iPhone and iPad with Apple silicon are pretty capable of running modern AAA games with a few tweaks, as are their computers. But they just won’t invest in making porting easier and cheaper and refuse to pay more devs to bring their games to the platform or to build a proper gaming division to support them. I’m convinced that Tim Cook just thinks gaming is for losers and doesn’t want it associated with the brand in any way.