I don't think something like Proton will pan out. What will likely happen is that the larger studio making AAA games will want an iOS port. At that point, it will be trivial to tweak it for the M1 chips. Games like Elden Ring and and GTA are perfectly playable on an iPad with a controller. M1 Apple TVs are definitely in the pipeline. iOS makes it worthwhile for AAA studios to port their hits over to the Apple ecosystem.