There are plenty of examples of cryptocurrency related scams that present themselves as a legitimate investment. Aside from that, I think an argument could be

There are plenty of examples of cryptocurrency related scams that present themselves as a legitimate investment. Aside from that, I think an argument could be made that bitcoin itself is a form of pyramid scheme. I'm not sure if I 100% agree with that, but I understand the line of reasoning. I'm glad regulators are looking into this and asking these questions.