I think that is a misleading quote. He made actual profits, albeit by unscrupulous (but legal and very common) methods. There was nothing like a ponzi scheme, the prosecution just wanted to say a crime that was well known at the time. Along the way he made false statements to investors, and he was so gross and unpopular they were able to get a conviction the "victims" were not even interested in, but only on two securities technicalities and only because the jury wanted to get him on something. He was acquitted of 5 other more serious charges.

This is a great example of a public show trial, where they basically make an example of someone while allowing companies to engage in the same disgusting behavior without any attempt to discourage it.