I think a bunch of people, without explicit coordination, were rude to the sorts of people who weren't seen as belonging. My experience jives with the article GGP linked, and I've played both parts (and for anyone who had to put up with me shit talking PHP, I apologize). It's a tale as old as time; people form cliques and gatekeep, c'est la vie. Rarely is it by explicit coordination (secret societies notwithstanding), but I would still call it a strategy.

Please note, I'm talking about the "contempt culture" specifically and not prickly nerds broadly. Some people are prickly and that's fine. It makes sense to me too that people with a complex and difficult job which is perceived as a cost center might be prickly for entirely different reasons.