And Apple is just getting started. I was amazed at how many Windows only games I could get to work with either CodeWeavers commercialized and drop dead simple to use WINE implementation or the Windows ARM beta running on the Parallels beta.
If Apples new SOC is able to woo more and more people like I think it will to run on Macs at some point developers will notice and the quantity and quality of Mac ports will improve and I may even not need Windows running on my Mac to run all the games I'm interested in. Most of the games I run today have Mac versions already (although that didn't factor into my buying decisions since as I mentioned I also have a Windows box).
I look at this similar to the Blackberry before the iPhone. The year before the iPhone if you would have told me that it Apple was coming out with a phone that would utterly displace Blackberry within the next five years I would have laughed you out of the room - but that's exactly what happened. Nothing is guaranteed, but I wouldn't be shocked to see a significant shift away from Windows for quite a few segments of gaming.