Why bother defending them about this specific issue though?
Either Epic is right, and this pushes Valve to improve Steam performance.
Or Epic is wrong, and then who cares? People will continue to not use the Epic store and continue to use Steam.
It just feels more "defensive" then "defending" if that framing makes sense.
People are fans of Steam (of Valve, actually) because Steam has been a boon for the gaming world and for Linux gaming in particular, in a way others (like Epic) haven't. I subscribe to this opinion. I'm just so glad gaming on Linux is mostly seamless now, I simply don't care anymore for which OS a game was built (within reason... but then again, Windows games are not guaranteed to always run on Windows either!).