The whole banking system is way more of a Ponzi than Bitcoin could ever think of being.
All money in the banking system is borrowed into existence. All banking system loans are creations of new money. How do we know? Here's how.
If you go to the bank for a loan, and you are sitting across the desk from a loan officer, and he/she slides the promissory note across the desk for you to sign, does the unsigned note have value? Of course not. If it did, the banker would simply loan you the money without your signature. In fact, the banker could pick a name and address out of the phone book, write up a loan to that name, and keep the money but charge the loan to that name.
The point is, the note has no value without a signature. Then you sign it, and suddenly the note becomes valuable. Value is in your signature. You just created value; you just created private money.
Then the banker accepts your private money, and gives you some public money in trade. Notice that it is in trade. There is no loan. The loan idea and wording is a lie.
The point is that the loan is a creation of new money. The bank sells your note, making money on sale immediately, and on your payments as you apy the "loan" off. No loss to the bank, even if you immediately default.
All money is created through loans. The government borrows money. Their credit is based on the ability of the country to make payments on the loans. Getting more loans for the banks is what the government does to assure that they can make payments on their loans and get larger loans in the future. Military spending comes from loan money, and that is why we have wars. (Another subject.)
The point is, if we don't keep on getting more people and companies into the Ponzi, and if they don't make payment on the outstanding loans, the Ponzi will fail. Who knows what the chaos would look like if the banking Ponzi failed.
Bitcoin is straight-out value for value, although a lot of it is perceived value. If it has a touch of Ponzi-ism in it, it is not anywhere even approaching a Ponzi like the humongous banking Ponzi.
To see the size of the banking Ponzi, consider that the Foreign Currency Exchange (Forex) does over $5 trillion in fiat currency exchange every day.
Any Ponzi in Bitcoin isn't even a blip on the screen... isn't big enough to be the proverbial needle in the proverbial haystack... isn't the size of a gnat in a bowl of soup compared with the camel that is the bowl.