Earlier quoted context omitted.
Let's assume they had the technical skills to do it So basically a nerd with social skills?
Please. For the purposes of this conversation a "nerd" means what the OP wants it to mean, which is at least "someone who knows what a 'graph' is". Whereas the technical skill required to build a basic electronic social network is "can you dial a phone?" Been that way for sixty years and more. For a dramatic musical rendition of the social networks designed by your parents (oh, wait, I mean your grandparents , maybe…
You're giving examples of people using social networks. I (and the person I'm responding to) am talking about people building the infrastructure to host social networks. Using your examples, the inventor of the phone and sms would be more appropriate.