I don't think anyone has forgotten; many just don't care.
It's part of a societal problem in many places around the world: sexism, male-privilege.
Tyson's violent past was already known in 1986, BEFORE he won his 1st World Title.
Everyone knew this was a 19 year old kid that had been arrested multiple times, had been in reform schools, and had mugged and beaten little old ladies when he was 13 and 14 years old.
At Tyson's peak in 1988, Larry Holmes was offered a pile of money to come out of retirement and challenge Tyson.
He was asked about the Mike Tyson phenomenon, and Larry knew about the sociopathic history and stated that Mike Tyson was no credit to boxing and would ultimately self-destruct, put himself in prison somehow.
Of course people got all p!$$ed off at Larry that time, shouting "jealousy"", because everyone was crazy about Tyson right then, Tyson was on the cover of loads of magazines, not just boxing magazines neither, and was in the news regularly for his Boxing accomplishments, and on tv shows and had endorsement deals.
Larry knew Tyson's dark past and wasn't giving him a by like all the millions and millions of fans did and continue to do.
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