The SEC has always been in place supposedly to protect the average citizen from being able to make bad investments - however I don't understand how they dropped

The SEC has always been in place supposedly to protect the average citizen from being able to make bad investments - however I don't understand how they dropped the ball so hard with crypto-"currencies;" regulatory capture by VC-finance industrial complex? Is it that they are global and decentralized that made them just not take a stance on them, also the same reason it obviously would easily and quickly gain popularity as a global, decentralized MLM-Ponzi structure?