The lesson here isn't "don't fall for scams", that's obvious, and it just takes a more sophisticated set of lies to trick smarter people out of their money (Enron + Arthur Anderson).

The real lesson is "don't use other people's money for your own schemes", which is exactly how he got rich to begin with. Banking taught him the opposite lesson for years. And voters couldn't care less about primary'ing politicians for banking regulation even after the mortgage crisis, so it will never, ever stop.