Its essentially the first blockchain certificate of deposit and hex was given free to any btc holders that signed a message with their eth address.
It is not a "certificate of deposit". It is similar to a bank paying interest with beanie-babies instead of dollars.
Hex is not a ponzi scheme. It is a sophisticated pump-and-dump.
When the staked coins are air-dropped on November 19, they will be become worthless because nobody will have a reason to buy them. Anyone that is buying hex now is going to lose it all.