That's a really interesting concept, but I think somewhat flawed. The purpose of regulating schemes out of existence is so that there's a smaller chance of them existing. Even if that decreases one's ability to discover these schemes, it should (theoretically) more than even out with the decreased chance of investing in a Ponzi scheme.

I liken it to online shopping. Online shopping today is much more trustworthy than 15 years ago. Improvements in technology and more name brand companies using the internet has led to an increase in trust levels for shopping today versus in the early 2000's. This does make us more likely to be scammed, but the fact that it is now harder to scam someone online has (I would assume) decreased the percentage of people making fraudulent purchases.