Until you can't. And that's the parallel right there: in practical terms, it's a scam for rewarding those that are insiders.
Bottom line is there is no exit strategy for 'suckers' who are meant to be left holding the bag. When collapse is part of the curve and denial is part of the sales pitch, it might not literally be an exact Ponzi scheme, but you're meant to be one of the smart ones hyping and profiting off the dumb ones who chronologically come after you. That's the profit strategy.
https://news.ycombinator.com/item?id=26203396