This is just something that's really cool and shows how much of an open platform Xbox is becoming. 

The Outer Worlds for Series S/X isn't a free upgrade. If you own the game and all DLC on the Xbox One you still need to pay to upgrade.

Think this is the first MS First Party game to charge to upgrade from XBO to XSX. Don't believe the original is an "optimised for XSX" title either.

Xbox and Paradox have a close relationship, I think this isn't the first that Xbox was involved in one of their announcement shows, should be a few Game Pass announcements.

It's likely cause Private Division (Take-Two) is still publishing it.

Private Division is still the publisher for the first game. MS is taking over publishing for the sequel, so this upgrade decision isn't from MS's end. 

I see. Well if it's on gamepass I will probably play it again as I never had the DLC. Otherwise not.

I'm not entirely sure the reasoning as to raise the level cap to 99 though lol. I guess to give you the chance to unlock every single upgrade in the game?

Atomic Heart becoming quite the hit with players! 

That's one of the few things I appreciated about New Vegas. Higher level cap! I don't like reaching max level before finishing an RPG, I want to always be growing.

Unfortunately it's not on Game Pass.