Basically, because cryptocurrencies aren't considered "money", and what they are is still kind of up in the air...and because, as so many of its proponents are

Basically, because cryptocurrencies aren't considered "money", and what they are is still kind of up in the air...and because, as so many of its proponents are so proud of (despite it being extremely obviously a temporary state of affairs), cryptocurrency is not yet subject to very many laws and regulations. You can't have the protections of "money" without the regulations of "money". As long as everything was going fine and government was still dragging its feet catching up to technology, the people who got in early got to pretend there was something special about cryptocurrency that made it possible to have their cake and eat it too. Now, they're starting to find out why that's not the case.