The MMM Global ponzi scheme has been operating in the open for about a decade: https://en.wikipedia.org/wiki/MMM_Global
Ponzi schemes benefit greatly from a public perception that "all markets are rigged". Ponzi schemes can feel like a rigged game where they have a chance to get in on the ground floor of a rigged game. They also benefit from false equivalencies such as "after all, nothing good lasts forever" to make ponzi schemes feel like just another bull market opportunity that won't last forever.
It's akin to gambling. Many entrants tell themselves they'll only allocate as much money as they have to lose, or that they'll withdraw their initial investment after the first 100% gain. Sadly, they usually get overconfident when the scheme doesn't immediately collapse and end up investing far more than they would normally be willing to risk.
Perhaps this should be a measure of a bubble too: when you ran out of names and you start using food to name financial contracts.
And just wait till you see what is going on with Decentralised Finance.
https://coinmarketcap.com/yield-farming/
Sort that by Highest APYs. It fluctuates all the time but the numbers are getting as high as 1,000,000% APY. There is no world in which that can be anything but a Ponzi scheme.
People are actually buying into these things.