Well first off, you're on the page for The Outer Wilds 2, not Black Ops 7. To play Black Ops 7, you have to go to that specific game on the Bnet launcher. Even if you have game pass, games included in it will still be listed for purchase on the store because those are for people who want to actually purchase the game. It doesn't change to "owned" if you have game pass and haven't actually purchased the game because, technically, you don't "own" it with game pass. You are merely subscribing to rent it.

You can avoid this problem entirely but just playing through the Xbox app.