All i know about this is that I would have prime, peak focussed Lennox Lewis as my betting favourite against any heavyweight (similarly peak/prime and focussed) in history. Some might be as close as 55/45 but I'd put my money on Lewis. His only real downside was the chin and that only seemed to be when he was unfocussed and out of sorts, and he avenged both of those. If it was a league table as well then i'd also heavily favour Lewis to end up with the most wins and least defeats. i'd say that's H2H goat.
I actually watch the fights and compare what I see. You cant argue Size but we disagree on the progression of skills in boxing in the last 60 years. I dont get to emotional. I have acceped Wilder as a top 10 HW. Before I had him like top 50 but he has proven himself against the likes of Washington, Ortiz and Fury. I look for Cold Hard facts to base my opinions. Any eras are different and relevant in ATG rankings but that is not the same as H2H. Marciano is an ATG but Would be a joke H2H against modern SHW's. Ali is an ATG aswell but Would be a tag runner att best in our era. Thats not hating just common sense. Lewis was best of His era but this era is bigger and stronger. Usyk is considered small but just compare His skills with Ali (around same Size) its Night and Day. I recommend to look Up breakdowns of techniques etc and see how much more boxers of today are doing compared to 60 years ago. The more you watch the more you Will understand and analyze fights. Chambers vs Washington is excellent to see how important Size really is.
What progression ? Actually explain in detail how heavyweights today pack more technical skills and posess better ring generalship than the one from the 70s. You're opinions aren't to be taken literally. Larry Holmes transported into todays era would still be the most technically sound heavyweight/cruiserweight with the best jab. He legitimately does everything better than Fury besides fighting from both stances, though Fury is larger.
But he was knocked down by Renaldo Snipes, who made Rahman look like George Foreman, so I don't think his chin is quite what you think it is. Lewis would not have struggled with Weaver, Snipes and Williams.