This a blatantly Ponzi and not different to normal Ponzi. Stating it that it was Ponzi doesn't mean you are safe for operating an illegal while your method is an illegal? Doesn't make sense at all. And the reason why Ponzi is very dangerous is because the operator can run all the funds that deposit to there wallet. So technically speaking, it's normal that an operator will get the money from other people to pay other people investment, This is same principle in trading.