All points are valid. I doubt you ever met a puncher who hit as hard as Marciano. Marciano didn't hit hard for a 180 or 190 lbr, he hit hard for someone who even weighed 240 lbs. Marciano had above mediore defense and it would be even better against a slow 6'6 250 lb shw. It is much easier for Marciano to close the gap and land on Joshua than it would be for Joshua to land on Marciano who would be bobbing down to well below Joshua's waist.
I was asking for prime wins. If we are counting wins over past prime fighters then Marciano's resume starts to look pretty good.
Because Joshua is big, strong, mobile, agile, and powerful enough, with a long enough reach, to play whack-a-mole with Marciano's head if he tries to crouch and crowd him. Other than that, it might work.
Joshua is not mobile or agile. Joshua has no speed to back up that reach advantage. No, Joshua would not "play whack a mole" with Marciano's head. Hitting on the back of the head is illegal. You are suggesting that Joshua would win using illegal tactics such as hitting behind the head.
Didn't mean that he'd literally pound Marciano on the top of his head. I meant that as soon as a crouching Marciano came within his range, Joshua would light Marciano up with more authoritative power than he'd ever encountered in the ring, and then reset by taking a couple steps back. And then repeat, for as long as Marciano is able to withstand the punishment. He's more than mobile and agile enough to leverage the extraordinary size advantage he'd enjoy in this one. Joshua could make this one a pretty easy fight with the right game plan.