> Steam is in the unique position to create a kernel anti-cheat

Valve has a long-term policy of being utter trash at game security.

> I know that's not popular. But they are the only ones with the install base AND ability to pull it off in a such a fashion that wouldn't be so god-awful.

Epic Games does fine (though they did it by purchasing an anticheat startup).

EDIT: Oh, you're talking about making an anti-cheat focused Linux kernel build? Meh, still would not trust Valve on that front given their long-standing policy of not giving a shit.