Ali is my favorite of all time. He was a Kawasaki Ninja surrounded by Harley Choppers. heh
I always want to convince myself that he's the best... or others.
But Robinson had a comeback in his late age too, even older than Ali.
I think 36, he knocked out Gene Fullmer with a perfect left hook.
He even almost defeated the light hw champion past this age, if it wasn't for the heat.
Common thought is that the little guys are supposed to age faster than the big heavies.
But Ali couldn't do anything by age 36, just barely get by
Jimmy Young, Spinks... I don't know how Ken Norton wasn't able to knock him out by then.

Ali could dance better than Robinson, IMO, but Ali was a freaking fast for his size compared to the usually slow plodding big guys. Robinson hit harder pound for pound. Maybe the hardest puncher out of the dancers in boxing history? Ali had the best psychological game. Robinson went to the body, Ali rarely did. Robinson was better at rematches. Ali had to come back from a three and a half year suspension... and did beyond any expectation despite his slower feet and less hand-foot synchronism. Robinson had his Jake LaMotta and Ali had Frazier (to be fair, Jake was naturally much bigger than Sugar, as opposed to Frazier being around the same weight as Ali... ehh but later Jake would complain of weight draining at middleweight). Robinson was technically sound, Ali was unconventional sometimes downright wrong (example: Sugar had a great left hook, Ali had no left hook, heh) Ali's rope-a-dope was insane, therefore genius in defeating a Achillies type George Foreman. Despite his failure at an aptitude test, I think Ali was special in the brain activity department. Robinson was the most intelligent boxer in boxing, but Ali just thought different... I mean the rope-a-dope eventually lead to his demise and parkinson's desease. Ali said that Robinson was The Greatest Pound for Pound, but he also said that Joe Louis was The Greatest. Ali learned from Robinson, but is it lesser of him to steal from other fighters or is it more of him to learn from the masters? IMO nobody, including little guys, looked as graceful as Ali. Robinson moved up in weight, successfully facing meaner, tougher, harder hitting, bigger guys. He didn't duck anybody in a golden age of boxing.

I once read that Jim Jacobs measured and compared the speed of both Jab's. Both fighters did all we could ask of them and more. I just think Ali was unusual inside the ring, not outside.