Besides, Steam doesn't slow down your game. These complaints about Steam are all nonsensical gripes.
I think he was referring to the lack of the LAA patch "slowing down" the game (at least negatively effecting performance for those who would have found it useful).
It is a fair complaint that this simple performance enhancer for those on systems that would show a benefit is now blocked. If they're going to block minor changes to the executable header they should offer a version pre-patched for LAA.
I'll admit that I've actually found the steam web browser quite useful, since I get poor performance outside of full screen. This way I can use the internet without Alt+Tab.