It depends on your interpretation, since there isn't a single actor involved. If you think everyone who buys into it knows what's going on (that it's a pump, and that the last people in are going to be the bagholders), then I'd argue it's not really a scam because there isn't deception going on (IANAL, THIS ISN'T LEGAL ADVICE). On the other hand, the posts I've seen definitely are not mentioning the risk aspect, and are advertising it as a get-rich-quick scheme. In that sense it's a scam.