Then there are the financial advisors. Last time I talked to one, the selling point was nothing but "trust us, we have a team of Ph.Ds."
[1] Check out people like skybridge capital as the most high-profile example https://skybridge.com/
[2] See for instance Buffett's bet against Protege Partners https://www.wallstreetphysician.com/warren-buffett-bet-sp-50...
[3] eg Bramdean's spectacular losses on Madoff https://www.ft.com/content/ea15b152-72f4-11de-ad98-00144feab...
The fact that would most likely be fraud and a breach of fiduciary duty for one thing[1].
[1] See for example https://gowlingwlg.com/en/insights-resources/articles/2015/i... The example they cite is from a closed-end fund but the same principle would apply to a hedge fund