While I agree that Lieb made this claim, I’m skeptical that it was accurate.
It’s is undoubtedly true that Cobb was an aggressive player, and wasn’t the most popular, but talk of his virulent racism is almost certainly untrue.
He actually supported allowing black ball players in the league. And by the end of his life, he was a big fan of Willie Mays.
That, too.
Also, Cobb and Ruth were rivals, but eventually became friendly, and played together in a charity golf match after they had retired.