About the only good thing about reckless misuse of the word "Ponzi" is that it advertises the speaker as an idiot whose opinion can safely be ignored.
A Ponzi is a scheme that pays new "investors" out of funds from older investors, generally with some implausible cover story portraying it as a legitimate investment. That's all it is. It isn't just a word that means any financial anything that the speaker finds shady for some reason. Used that way, what it means is "I am an idiot."
We already refuted that semantic shell game obfuscation delusion. See the thread that I quoted from. Numerous prominent Libetarians and Austrian economists have weighed in on this in agreement with me, such as Peter Schiff and Gary North who is a key advisor and long-time close confidant of Ron Paul, Lew Rockwell and the Mises Institute.
I hope you realize they are both Ponzi bubbles, but the fiat one will be the last one to crash, because both require a collapse of confidence and a supply of greater fools. The QE is ending up as dollar bond issues in the developing world, and they have a lot more undeveloped areas to soak up more debt than Bitcoin will have greater fools willing to pay $10000, $100000, or $1 million per 1 BTC (depending on which price the crash occurs).