Earlier quoted context omitted.
You may find it pleasant to have people around and water cooler conversations, but many others do not and have no need or desire for work to double as a social outlet.
It's not (just) about social outlet, it's about growing and learning professionally. Unless your job is to blindly implement features someone else adds to a spec sheet it's always worthwhile to get professional input from people from different fields. Often they'll have unique ideas and insights that comes from having a different background and different experiences.
Just because you (the person before you, actually) are a reclusive jerk, doesn’t mean everyone else also hates people and chitchat.