Haven't seen much new Xbox stuff worth mentioning today, but on the Nintendo side it's been confirmed the Breath of the Wild 2 will be in the same basic Hyrule as before. There is also a massive amount of backlash to the announcement that only Pokemon in the new games National Dex (basically this means the available roster in the new game) can be transferred into Sword and Shield, meaning that many Pokemon will be cut entirely. On top of that, they implied that they won't be patched in later, and that this is probably the philosophy going forward for the mainline Pokemon games.
I see nothing coming out of Microsoft these days that they are at all against multi-platform releases. At this point I honestly wouldn't be surprised to see MS games on a Sony system. It seems they are open to literally putting them everywhere.
So far it seems like they're willing to put games on other platforms "where they fit". Minecraft Dungeons makes sense on all platforms because the other games in the franchise have been and the series is super popular still. Cuphead only came to Switch where it was highly requested, and I'd say 2D platformers still get the most life on Nintendo consoles. Super Lucky's Tale wasn't actually a Microsoft game.
Then we have games like The Outer Worlds and Psychonauts 2, which were prior contracts that were in place when these studios were bought. While they probably could pull a game from other platforms if it doesn't already have a publisher or with a big enough check, it would cause extremely negative reactions from the gaming community as a whole, much like we're seeing with the games on PC the Epic is scooping up.
If we were to see a huge game like Halo: Infinite or Gears 5 on the PS4 or 5, I think we'd be in a different ballpark, but for now I think it's mostly smaller indie games that are what can realistically make the jump, and we just have to see PC as part of the Xbox ecosystem now.