The issue with the Zenimax acquisition is that their games don't really plug any gaps in MS line-up. They had Halo, now they have Doom and Wolfenstein too. They had Obsidian and now they have Bethesda also... Its doubling down on the same markets and setting these brands in direct competition with each other.
Its good in a way because it does help to differentiate the platforms, but on the other hand its a disincentive for anyone new try and break into such genres because the market is such a bearpit.
If you are developing a FPS, how are you supposed to compete at retail when Halo, Doom and Wolf are available day #1 on GamePass for both Xbox and PC? If you are CoD or anything else with a pedigree and following its not an issue, but for smaller teams/new IP's... Yeah, that don't look like a good spot.