Ali did transcend the sport because of tv exposure, that's how the world got to know him. They saw him talking crap on tv and were hooked [much like Mayweather].
Ali also had fights everywhere. He would fight in Africa, the Philipines, etc, he didn't simply stay in Vegas or New York.
With that said; the boxer who most transcended the sport was Joe Louis. Not because he talked but because of what he did outside the ring [long list]
But those days are long gone, the people who saw Joe Louis fights are AT LEAST 90 years old [80 years old would have been babies].
The people who saw Ali are about 50 years old or older [40 year olds were babies]. This means that those who saw Ali are the people who are in charge and the people who raised us, the people who saw Louis are either dead or in an asylum.
Time erases everything
Ali was more famous than Robinson because of his persona, the controversial social and political views that surrounded him, and the fact that he was a heavyweight (the general public has almost always found the heavyweight division to be the most appealing).
Ali is the greatest of all time. Why? Because he is recognized as such. You can be the most skilled boxer in history but you can't be great and influential if people don't know who you are.
There is more to life than boxing, and Ali is/was bigger than life. Sugar Ray Robinson was the best boxer in the history of the sport. Ali is/was bigger than the sport of boxing.
If Ali even said Sugar Ray is the best pound-for-pound boxer ever, then why does he not transcend the sport globally the way Ali did, who transcended the sport without tv exposure or the need for sporting any commercial brands on tv, just his plain persona did it all.
