It makes sense for them to have contracted Redfall as an exclusive since it would probably not have made as many waves as a multiplat game (Deathloop was probably the same bro-shake deal,) and Starfield as a major new IP is a nice crown jewel for Xbox when they are in need of exclusives to showcase (even if it's still a year away and two years after the competition started launching its own "next-gen exclusives") Going exclusive with these are the smart, straightforward, and seemingly obvious choices.
IMO, the factors that weigh on those decisions will be given more discussion when it starts coming down to known IP like the Outer Worlds 2, Indiana Jones, whatever Doom or Wolfenstein is next, Elder Scrolls VI of course.
What's nice for MS is that they have all the cards here. They can make these games throughout development without having to decide on platforms yet, having all their meetings behind closed doors and analyzing the market trends to decide between Xbox exclusivity versus brand saturation, and then in the last day that they have to decide before going public, they can just say, "So, should we also push the PS5 button on the compiler? ...Naw, fuck it!" They can make that call for each one of some of the biggest AAA adult-skewing brands on the market for years to come (and they can also make both choices, by being exclusive for a time to get the most juice then dropping later on other platforms like Stadia and Luna and Facebook Cloud Games and, oh, also that Sony box that looks like an air conditioner)... with the Bethesda library, whatever they choose, they win.
It does if they're less concerned about competition and more about expanding its profile. Exclusive games help move Xboxes, but the long game for Microsoft is beyond the box.