Not sure if you're being serious, but at least Riot Games' anti-cheat Vanguard always wants to be running in the background, whether the game is running or not. Sure, you can stop it, but if you then want to play something that requires it, you have to reboot. There's no manual way to start it.

One of the reasons I decided to drop Valorant.

Valorant’s anticheat always runs in the background, even when the game isn’t booted. There’s a reason people call the game spyware.

but why would anyone be loading more than one game at a time?

Maybe you're virtualizing it for multiple users. Sure, that might sound like a weird thing to do, but that's mostly because shit like this makes it harder than it ought to be.

i routinely have 3 games running in the background, sometimes 4. Different strokes and all that.