Let's say I run a swap meet for people to buy and sell Pokémon cards. There are lots of scammers out there, but I promise people they are going to get good prices. And I even offer to buy cards off of people at good prices to drum up interest.
Tomorrow, the SEC decides that Pokémon cards are securities (far-fetched, but work with me here) Suddenly, anyone buying and selling them becomes a criminal. I tell people via text message "pish-posh - there's no way the SEC could enforce this". But people stop coming so I promise them that I can buy up all of their cards anyway. Especially the cards that complete my collection.
Then it gets enforced. Not only did I trade in illegal assets, I am now guilty of fraud for telling people it was safe. I am also guilty of market manipulation! And on top of it, I did it via text message so it's now wire fraud to boot.
As far as I understand reading the charges, this is mostly what he is guilty of. This is a bit different than the "true" type-1 frauds that exist in crypto - the blatant pump and dump schemes, et al. In fact, I would feel safe to say there might have been no fraud without the SEC classification. (EDIT: Ignore this since they also did a lot of legitimate fraud too)
Regardless, the writing is on the wall for crypto. I could not even fathom why you would want to be holding onto even Bitcoin or Ether right now.