I think the hardest battle is going to be with anti cheat. The anti cheat that developers want basically requires dystopian levels of restrictions which are against everything valve has done on SteamOS so far. Personally I'd love if we all just went back to playing on personal servers with your real life friends or people you otherwise trust. But I don't think this is would go over well with the average online gamer.
If anti-virus software can function in user mode, anti-cheat software can too. https://www.theverge.com/news/692637/microsoft-windows-kerne...
Just seeing all the gamers requesting a kernel AC for CS2, saying VAC does not work; but now they have banned a lot of cheaters and seem to have less cheaters than the new Battlefield which has kernel AC.