I recently saw the game called "Bongo Cat" on Steam which monitors yours keystrokes and accordingly plays the bongo drums. I saw that it was not working properly on Wayland because it does not allow the game to record keystrokes from other apps.

This got me thinking; how does ~~Steam~~ Valve protect us from malware? I was searching for "steam games malware" on DDG and found out that there were a few incidents regarding this. I understand that Steam probably has a robust mechanism for understanding game behavior but it's kind of a black-box for us.

Is there any independent vulnerability checker for games? How paranoid should one be before downloading games from steam?

PS: I know that as Linux users, most attack vectors don't work for us but it's good to be aware just in case.

Edit: I need to clarify. I know Steam is just a game-launcher, it's not supposed to protect the user after the game is installed. I meant to say how does Valve protect the user from malicious games? Is their mechanism known?