In retrospect, you could definitely see that some people came from bad social backgrounds (and thus didn't wear the best clothes for instance) that were just there because they were so smart. But for instance there was also a guy from a very privileged background who went to private school (yes, clean clothes, confident and good at sports) who was actually a jerk. Anyways, there were also fairly average appearing people.
What I want to say is, I think the whole observation is very skewed. People from not so privileged backgrounds are usually not that visible, but just because of a high IQ might enter opportunities (university, job, social circles) that might be otherwise inaccessible und thus they get into the spotlight.
My FAANG experience is that people like outdoor sports and going to the gym too, I wonder where all the Linux con t-shirts and drinking Jolt cola people went…
Someone who is great at sports will tend to focus on that. It's just natural to direct yourself towards pursuits that come easily.
The problem with this thing of course is that it's self-enforcing. Less experience with social interaction causes even less ability. In the end that can lead to psychological issues. It did for me too, but I was really helped by my therapists and put back on track <3