Is there a causal link between being relatively lonely and isolated during school years and (higher chance of) ending up a more intelligent, less shallow, more successful adult?

Imagine that you have a pre-school child who has socialization problems, finds it difficult to do anything in a group of other kids, to acquire friends, etc., but cognitively the kid's fine. If nothing changes, the kid is looking at being shunned or mocked as weird throughout school. You work hard on overcoming the social issues, maybe you go with the kid to a therapist, you arrange play-dates, you play-act social scenarios with them..

Then your friend comes up to have a heart-to-heart talk with you. Look, your friend says. You were a nerd at school. I was a nerd at school. We each had one or two friends at best and never hung out with popular kids. We were never part of any crowd. Instead we read books under our desks during lessons and read SF novels during the breaks and read science encyclopedias during dinner at home, and started programming at 10, and and and. Now you're working so hard to give your kid a full social life. You barely had any, are you sure now you'd rather you had it otherwise? Let me be frank. You have a smart kid. It's normal for a smart kid to be kind of lonely throughout school, and never hang out with lots of other kids, and read books instead. It builds substance. Having a lousy social life is not the failure scenario. The failure scenario is to have a very full and happy school experience and end up a ditzy adolescent. You should worry about that much much more, and distribute your efforts accordingly.

Is your friend completely asinine, or do they have a point?