The Securities Act and the Exchange Act give the SEC broad latitude in regulating securities. The fundamental question is: is Bitcoin a security? The situation now is a bit like if the SEC tomorrow said Harry Potter books were securities, would bookstores suddenly become unlicensed securities exchanges?
Basically all of crypto passes Howey test for securities:
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an instrument qualifies as an "investment contract" for the purposes of the Securities Act: "a contract, transaction or scheme whereby a person invests his money in a common enterprise and is led to expect profits solely from the efforts of the promoter or a third party."
I agree. All of crypto passes the Howey test for securities.
Bitcoin doesn't match that definition though. Who or what entity is the 'promoter' or 'third party' for Bitcoin? There's no registered entity, no (legitimate) foundation, no company, no CEO, no board, no chair. It's just a protocol.