I don't think of this as a blow at all. The ICO extravaganza has come to the point of the ridiculous. Many of the ICO's still have not got anywhere near their claimed product online yet. Many have had the money disappear along with the scammers who ran the racket.
I doubt that these ICO rackets would have worked no matter where they were domiciled. This is partly also why most of them use a cryptocurrency, and registered companies in known havens...
Note that this only directly affects ICO's, and not cryptos. Yet. But I personally don't see the problem either that schemes like Steem would be under investigation not far further down the track, because, and admitted in the words of none other than Dan, himself, devised to skirt around regulations while allowing the founders to amass a large amount of tokens then trickle out to the market to actualise their 'value'.
You don't wonder why so many promises are made by Steemit and then nothing ever happens?
I'm not saying that I consider the SEC a competent, uncorruptible investigative agency, far from it. But the sharks smell the blood in the water. They of course will line up to steal the money before the many racketeers manage to escape with the money after the half-assed 'work' they did to create the appearance of a legitimate crypto system.
RE: SEC to blockchain community: You are now regulated