Mostly just Valve specific software implements to make the experience better. SteamOS has a really good suspend/resume sleep feature where you can just power off the Deck during a game like any other console, then when you hit the power button again it just lights back up to where you were in the game.
Not sure if that's in any other distro
I'm all for people buying what they enjoy playing, so if someone genuinely enjoys CoD I'm excited for them that they get some new stuff to play.
What I don't get is the constant group of people buying it every year and complaining. Like, guys, if you don't like the product you're buying, stop buying the next product from the same place until they fix what you hate about it.
There's literally tens of thousands of video games out there. You'll be fine if you don't play one of the most creatively bankrupt franchises in the industry, I promise.