That’s unfortunately not how re-investing incoming money works.
Gaming on Linux only has a future because Valve used “windows money” to bring it alive.
Gaming on Mac, right now, has no prospects. And as it’s proprietary, the only corporation that can really change that, is apple. There is no reason to spend on it. Is that fair? No. Small minorities of users get screwed all the time.
And apple is just as quilty of business decisions that screw a few users by taking things in a direction that’s better for the company and the majority of its customers.