If you have 1 billion on spare money, you can easily replicate their "black-boxes" strategies for fun. Some of my ML research work (I work for a hedge fund) points exactly on their trading behaviors and relations with different instruments during the past 25 years. Is not fraud or insider trading, is just everyone involved in the economic world benefits from this, that there is no real incentive to call it fraud.

PS: If you have 1 billion to invest, call me ;)