Gm Nostriches, watched madoff (finally) and really enjoyed it and turns out, #bitcoin is absolutely not a Ponzi, but also helped me realise important cross overs that cause problems when speaking about Bitcoin to notmies/loved ones:
1. if you don’t know why it has value, don’t invest.
2. If someone holds your coins and restricts your from withdrawing, say gfy
3. If people are shilling yield products saying they use it, also say gfy
4. If you don’t know why a product generates yields, stay away.
5. If a regulator gives a product the green light, stay frosty, then say gfy
6. Don’t believe it is legitimate just because “reputable” entities are putting their money into it (they’re shysters and gamblers)
7. If people tell you how much money they’re earning, ask them to explain it.
8. Don’t invest more than you can afford to lose (but more precisely, more than you can afford an 80% haircut on.

Think that’s about it, so no, bitcoin isn’t a ponzi, but realise there are some characteristics we may use to persuade others to buy bitcoin that are no different to a ponzi, so get informed and act appropriately. 

There are no solutions, but I’m gonna stay with “it takes quite a bit of work to understand, if you’re willing to put in that work, you’ll be able to decide yourself whether now is a good time to buy”. Peace.
https://m.primal.net/MBiu.jpg