I'm going off-topic to the original post - to which I apologize.
I consider Apple and Microsoft as "frenemies" - they'll collaborate when they feel it benefits both of them, and compete when they don't. Yes, they cross license and invest.
Microsoft "could" do a lot of things. To date they have not made any move to easily provide or support Windows 11 ARM on anything but Surface and OEM ARM PCs. Ball's in Microsoft's court.
Yes, 6M Macs per quarter may be sold, that does not mean that third party developers providing their software on the Mac platform feel it's as profitable as coding for Windows. Last quarter that "6M Macs" represents less than 10% of the total shipments - Windows being the rest. "Show me the money".
Perhaps this is why Apple is making their push for macOS compatibility with iOS applications and their switch to Apple Silicon - where the economies of scale favor the Apple ecosystem and where developers can leverage them by developing both for macOS and iOS/iPadOS.
Since when has Apple been seriously focused on the gaming developer?