Those two examples are why I say the fight between Ali vs Tyson could go either way. Let's not forget Ali beat Foreman by wearing him out with the "rope a dope", then knocked him out. Let's also not forget Ali won 2 out of his 3 fights with Frazier.
1. Tyson knocked men "twice" his size off their feet with ease. He mastered the ability to counter punch and slip inside instantly at the same time and once inside, your size advantage was GONE.
2. Tyson was the most explosive boxer in history. Also the hardest punching. Ali was faster, but his punches only packed half the power of Tyson.
3. Tyson lost his mental edge after he lost his first fight. Before he lost, he truly thought nobody could beat him. Like literally believed it 100% and it showed in his fearless inside game against much larger opponents. The power of suggestion ruled his mind and it worked for him.
4. He trained harder and maximized his God given talents better than any fighter in history.
Go watch some Tyson fights in his prime. Nobody else out there like him. Yeah, I know the arguments, he had some easy fights moving up. Well excuse me these were against guys twice his side, that knew how to fight and would kick the living shit out of the average dude in any bar fight. Tyson ran through these guys day after day in 1-2 rounds. Literally knocking the living shit out of these big brawlers. Most people can't do that.
I believe Tyson in his prime, would have easily defeated Ali in his prime. As in very easily.