“Games you’ve bought from the Epic Games Store are first-class citizens, too”
The only reason you can play some games from EPIC is because of Valve with their proton and the free labor of Linux users. That quote doesn’t make any sense. Vote with your dollar and avoid their store if you want Linux gaming to improve.
Valve didn’t exactly make it difficult to run additional software to accomplish this. Extra steps for sure, but far from being restricted.