Ali was arguably the greatest heavyweight boxer ever. I say arguably, though I’m not really qualified to argue, I don’t know much about boxing or the history of boxing. But people who do, say he was the greatest ever. So maybe he was.
What he was, inarguably, was a radical with a platform. Much like Martin Luther King, he was, for a period, simultaneously, both the most hated and most loved man in the US. As the Viet Nam war became less popular, in both the early ’70’s and after the war was over, that shifted to mostly loved. He was an icon. He was one of the most important people in the US in the 2nd half of the last century. The attention is well deserved.