There was a time when the US Congress tried to prevent complexity in financial products. The Utility Holding Company Act limited utility ownership to a tree depth of 3. This was in response to a mess created by Samuel Insull in the 1920s. The Glass-Stegall Act kept banks and brokerages separate. All that ended in the 1990s, because the banking industry managed to convince or pay off enough legislators to get the idea accepted that risk was now quantifiable.

Economists fell for the myth of Black–Scholes. This is a neat way of quantifying risk, but it assumes that risk has a Gaussian distribution. Sometimes it doesn't.