If the version of Joe Louis that fought against Marciano faces the version of Ali that fought against Larry Holmes, who do you think will be the winner and how do you see such a match between these two great fighters well passed their prime? The comparisson between them would be: Ali age 38 vs Louis age 37 Ali 217lbs vs Louis 213lbs
Louis's form was atleast somewhat decent coming into Marciano fight he'd beaten Savold, Bivins, and gave a decent account of himself against a prime Marciano especially with the jab. I think Louis had more left in the tank than Ali at that point in their careers and would win a decision. Ali was absolutely awful in the Holmes fight he had an overdose of thyroid medicine to get his weight down and was physically not fit to fight along with the early stages of parkinsons.
Second best fantasy matchup of all time behind this: https://www.boxingforum24.com/threads/1923-sam-langford-v-1981-joe-frazier.657001/
The Ali of the Berbick fight (81) beats that version of Louis silly. The 1980 version of Ali was depleted from bad medical advice and supplements.
I agree with the consensus that Louis had more left at this hypothetical point, and that would be the deciding factor.