This sort of ret-con of highly divergent and localized success is extremely dangerous theorizing. You rush to coin the term and concept (“First!”), but present no behavioral evidence to support the theory behind it. With a single data point (“Snapchat is popular”), you’re falsely suggesting that this theory is why. Moreover, you don’t even acknowledge the more likely scenario: adoption was driven by the ephemeral, sexting-focused feature set and that the design has been an inhibitor to success that “sharing” was lucky enough to overcome due to sheer adoption desire.
Rushing to coin a phrase while deferring the “research” to others is dangerous, and frankly bad advice to startup designers everywhere. I’ll be happy to embrace this concept the second I see some empirical evidence of its actual existence.