Great fighters get away with more nonsense than other fighters do, thats part of what makes them great.
It's not rocket science and it's not new.
Marciano is a legend and he was some kind of filthy brawling mongrel in the ring, but it worked for him, it was part of his style and it certainly didn't stop him from dominating most of the 1950's and creating a lasting legacy of pugilistic greatness.
Pick out ANY of the great fighters and you will see them get up to mischief in every fight at some stage.
They seem to know which side of the opponent the ref is on and they throw something low, late or into the back of the head and it doesn't get picked up while they hold their opponent and roll them the other way from the ref.
They find devious ways to infect the other fighters psyche and get an edge.

This is not tiddlywinks folks, this is attempting to beat your opponent in physical combat and if it means causing them pain, causing them to bleed, scarring them or rendering them unconscious then that is part of the deal as soon as you step through the ropes.

I think Ali was the Greatest fighter of all times, no question.
Did he use dirty tactics when he needed to, when it suited him, when he felt like it?
Damn right he did.
I still feel for poor old Ernie Terrell. What Ali did to Ernie Terrell was FAR worse than calling Smokin' Joe an 'Uncle Tom'.
Gee whizz he called Frazier a name, get over it
Even his trainer used dodgy tactics when he got in trouble. (Henry cooper)
It just adds to the stories, mystique and legend that is the the man we have come to know by a title beyond any boxing belts, he is
THE GREATEST FIGHTER OF ALL TIME.

Theres no second place in boxing.
There's a winner and a LOSER.
Which one do you want to be?
I know which one I want to be and I've hit opponents late, low and in the back of the head, I've butted them in the face and thumbed their eyes all of it intentional at times.
Not often, but when I needed to I did it and sometimes it worked, and other times I got points deducted, because ... I wasn't a 'great' fighter like the fellows we discuss so flippantly on here.

Muhammad Ali was like no other fighter because he overcame ENORMOUS personal, cultural and physical difficulties over a vast career where the best frickin years of his career were stolen from him because he was a voice for change that kept winning in the ring.
Unbelievably gifted with lightning fast hand speed and sharp quick footwork. His defence was impeccable and his movement just poetry in motion to watch. His conditioning was unparalleled. He created an entirely new style that has only been adopted successfully by the few very best fighters of later generations.
He fought 15 round contests all over the world in dozens of countries.
He went to the well more than almost any other fighter in history, and he did it all under a previously unequalled level of global scrutiny.
He was the first to smack talk with poetry etc.
He became elevated above the fight game and became a phenomena, a globally mutually revered and despised gladiator.
Greeted by world leaders, monarchs, he was a hero for millions and millions of people, like no other sports person has ever been before or since.

Did he get up to mischief and get away with it, YEAH!

So what?

It only added to his greatness, and no amount of latent misguided cheap shot negativity is ever going to change that.