Are we really pointing out that discard is bad in the mid to late game? Like, does that actually warrant posts? I kind of thought that was something that everybody just knew.

People play discard because it's really good. In general, but even moreso in a deck where a large part of your success hinges on resolving a single card. While most Survival builds don't run anything to actually hunt up Survival (E.Tutor and to a lesser degree Top do this), we run discard and Witness to ensure we get the ones we do draw on to the board.

Discard is good against absolutely everything. Seriously. You need discard to fight combo. You need discard to fight control. You need discard to fight graveyard hate.

I'm not saying RGW versions of Survival aren't viable, but you'd better be packing something else to compensate, like Aether Vial.