Being licensed as a money transmitter has nothing to do with with crypto trading regulation. In fact many of those licenses explicitly state such:
>Coinbase, Inc. is licensed by the Virginia State Corporation Commission as a money transmitter, but such license does not cover the transmission of virtual currency
On top of that, we're talking about the big players like Bitfinex, who created USDT simply so they didn't have to comply with any sort of banking laws, let alone securities trading regulations.