The whole point of these scams is to convince people to buy assets that nobody wants, but you convince them that some other guy really wants it a lot and will pay more for it in the future. And of course if he could convince some new guy of the same thing he can even sell it at a profit, but since there ultimately is nobody who wants this asset the chain has to break sooner or later.
Very interesting, and real estate and stocks, whilst subject to bubbles, are not Ponzi schemes.
But the US could end social security tomorrow and as long as it still required taxes and tariffs in the form of dollars, the dollar would still have value.
USD and other fiats are doing the same. Just at a much slower rate.
Edit:
It's basically just the Cantillion Effect[1] by another name.