It&#x27;s great that the author decided to do this work. 
TL;DR: The Dunbar numbers are significant for online social networks too.<p>People working in TCS on &quot;social networks&quot; often work with TCS tools, which are inherently asymptotic.
Thus they conclude some stuff on social networks, while assuming that the number of &quot;friends&quot; per person tends to infinity, without seeing much of a problem concluding that it&#x27;s what happens in &quot;the real world&quot;. 
To be fair, one excuse is that more realistic models are often not mathematically tractable (yet), but it doesn&#x27;t excuse making wild conclusions.