Ali was one of the best pure athletes ever to earn his living by boxing. That, however, is not the same thing as being one of the greatest prizefighters. I don't picture him lasting more than seven or eight rounds in the ring with Joe Lewis for instance. The two best prize fighters of the last forty or fifty years are probably Roberto Duran and Roy Jones.
Don't be "wediculous"!
I think that Ali is the overrated athlete of all time. He was blessed to compete in an era where boxers were regarded as royalty. ESPN and the other sports channels weren't around then so we just had to go by what the press told us.
It also helped that Howard Cossell was a rabid fanboy.