In a startup you want to actively screen for candidates like this. Someone who idolizes technological "purity" above all else and looks down on business will never be happy at a startup that needs to get shit done quickly. It's a lose-lose situation. They'll eventually grow resentful and quit, or you'll have to manage them out. Better to avoid the whole thing in the first place, no matter how great a programmer they are otherwise.
The only comment on HN more tiresome than "lol I can build twitter over a weekend" is a comment by a throwaway implicitly claiming that fixing the twitter product problems is easy.
Sour grapes, more like. If simply asking how they'd work with people from diverse backgrounds was triggering enough for this person, the process worked perfectly in rejecting them.
Commenting on HN is settled. Quarterback, armchair, they call it that.
-- Have you talked to a human? One of the action steps is to not be a know-it-all.
Alas, sentences with two commas, is what you have.