I think you are not understanding introverts. Social interaction is extremely draining for us, so we carefully manage that energy for interactions that also offer a lot of value in return, e.g. friends and colleagues. If we can reduce unnecessary interactions, this leaves more for being social where it’s valuable, making it possible for us to be pro social.

I love parties, deep conversations, etc. but as an introverted person, a day of excessive unnecessary interaction makes those interactions I do enjoy no longer enjoyable, and just a chore. By managing my social energy I am able to be a warm, friendly, and outgoing social person. If you met me at a party you probably would not guess that I’m introverted, because I am not antisocial.