If it was a Ponzi scheme then surely AAve and Compound would not have been shill in the largest crypto communities in the world. Binance only offers a Staking service with an interest rate quite similar to the bank rate and it is nothing special. The interest that large Defi projects are paying right now is because they make a lot of profits on their DEX. You know, in DEX the transaction fee is always higher than CEX and therefore the profit they pay will be higher.