A person that calls Bitcoin a Ponzi scheme either doesn't know anything about Bitcoin or doesn't even know what a Ponzi scheme is, or both.
A Ponzi scheme is a fraudulent investment operation where the operator, an individual or organization, pays returns to its investors from new capital paid to the operators by new investors, rather than from profit earned by the operator. Operators of Ponzi schemes usually entice new investors by offering higher returns than other investments, in the form of short-term returns that are either abnormally high or unusually consistent.
Nothing in that quote applies to Bitcoin.
Bitcoin is not fraudulent. It is 100% transparent.
Bitcoin has no operator.
Bitcoin does not earn a profit and it pays no returns.