There is a huge irony to Twitter using LinkedIn as a punching bag. Twitter is full of people pretending to be cool and popular and witty by doing things like making fun of LinkedIn posts for being fake.
I'm playing the role of the the smart one who thinks they have it figured it all out, and you're playing the pedantic one, right?
I definitely adopt a Hacker News voice when commenting here. But in my experience both HN and Reddit are different from most social products because I engage in lots of disparate conversations rather than having to to present a consistent personality and be building a brand and set of followers.