Microsoft has been steadily moving away from backwards compatibility and trying to be a one-stop shop for everything. They just want Windows to be focused on data collection and spying at this point. And your gaming data isn’t as valuable as you might think.

If they don’t have one for it already, they’ll just want to make a compatible Xbox app to run on Linux. If Linux can serve the gaming folks, and they get their data with an Xbox sign-in, it’s way less work and cost for them to keep Windows running the games well. I doubt they feel threatened at all.