There's a general rule that if a Microsoft brand has to make an announcement, it's because people are correctly detecting a trend...

The "we have no plans to retire X" announcement it's, annecdotaly, always about four years before they retire X.

So if my bullshit rule holds, we stop seeing cross platform support from games made by any studio owned by Microsoft in about four years.

It's almost like letting big companies swallow up each-other is bad for everyone except C suite executes.