[Unforgiven]

Joe Louis was badly over-the-hill.
Charles was way past his best too.

For the vast majority of fighters, 37 is just plain old. Then, now, whenever. 37 is generally OLD OLD OLD for any boxer. And Louis was a typical case.
Maybe Walcott was an exception, perhaps Archie Moore too. But Louis was clearly little more than a shell at 37. And Ezzard Charles had lost his mobility in the legs, at 32/33. Clearly.