https://themobmuseum.org/blog/did-frank-matthews-get-away-with-it/

In the third paragraph, it says Matthews earned $100 million in 1971. I think that’s why the other kingpins and American Mafia couldn’t touch him. He was just making way more money compared to any individual in the crime world at that time. Unless someone shows me different. He also cut out the American Mafia from his business and proved he did not need them to be the most powerful person in the underworld. And to put this in perspective, Carlo Gambino was the top boss in the mafia during this era. One of the most powerful and richest bosses in American mafia history. Even he had to backoff when Matthews threatened retaliation for tipping the feds off about him. Any other person and it’d be over.