i am not sure if this makes sense, but when i read your comment i wondered if part of the difficulty of finding friends is that smart people find it difficult to associate with people who are not as smart as them or do not have the same interests as them, and thus the problem becomes one of selection.
Maybe, and I could see this for top 1% people but I'm not that smart :)
For me its a time management thing, I am unable to figure out how to manage time for my own activities between looking after kids, working remote and just sitting around wasting time.