It doesn't have anything to do with crypto per se, it could be any product. Years ago a celebrity was found to have not used a product they were paid to promote and their was a big upheaval about it, that brought about The Truth In Advertising Act.
https://www.ftc.gov/tips-advice/business-center/guidance/ftcs-endorsement-guides-what-people-are-asking

As far as crypto's being a security the SEC has already determined that they are:

"There should be no misunderstanding about the law. When investors are offered and sold securities – which to date ICOs have largely been –they are entitled to the benefits of state and federal securities laws and sellers and other market participants must follow these laws."

https://www.sec.gov/news/testimony/testimony-virtual-currencies-oversight-role-us-securities-and-exchange-commission