OnChainFX has it listed as a Scam on their site, but with the caveat that no evidence to the contrary has come forward. https://onchainfx.com/sector/scams

It's definitely a ponzi-pyramid hybrid. The reasoning that its a scam is that if they were somehow able to gain such high percentages, why would they need to borrow from others, and instead just take a loan from a bank? The answer is of course they can't.

On the other hand, I can see the argument that in a market, few people gain and most people lose, while in a ponzi scheme, only the people at the tail end get hosed. Whether those running a ponzi scheme get in trouble for it, depends on whether they screw over someone important enough to go after them.