Size only matters up to a certain point. At 175-180 or so, you get into the territory where size begins to matter less and this is especially so at 200 lbs and above. This is why many would pick say Walcott to beat Lyle. And we don't have to imagine too hard because the 220 lbs Lyle was actually beaten IRL by a Walcott sized fighter in the person of Jerry Quarry. We see with punching power, a guy like say Bob Satterfield who hit harder than say Muhammad Ali. Even though Satterfield was 175-185 pounds and Ali 210-215. In fact, the relatively diminutive 5'11 200-205 lbs Joe Frazier hit harder than than the 6'5 250-260 pound Buster Mathis. And stopped him as well. Of course, weight matters the lower you go. So even a devastating featherweight puncher won't hit harder than a relatively light punching light heavyweight. Just like a 115 pound ATG fighter likely wouldn't beat a mediocre 210 lbs heavyweight. But a 185 pound ATG fighter like say Ezzard Charles could box rings around a mediocre 210 pounder. Even though they are both smaller than the 210 pounder, at 185 lbs, the smaller man is big enough where other things can make up for size and big enough where he can hypothetically hurt the larger man. Also, a washed up antique, belonged in an ancient history museum 215 pound Evander Holyfield beat 310 lbs Valuev who was in his prime. Well arguably anyway. The point is, smaller fighters of 175 and up can hypothetically beat larger men, depending on the individual fighter.
I think the power comparison is flawed. If we compare two punchers, bigger guy will usually punch harder (can't say always cuz I'm not sure). No point of comparing Bob to Ali. Ali threw a lot of arm punches, he wasn't a puncher. Compare Satterfield to Cleveland Williams or Ron Lyle. Not everyone is a puncher. Some fighters simply lack pop. The same way Paulie Malignaggi and Miguel Cotto weighed the same but one of them was a much more devastating puncher. Paulie could've been 20 lbs bigger and still might not be able to match Cotto's power. Mathis wasn't a puncher either. Compare Frazier to David Tua. Left hook artists. Who hit harder? Compare the right hand of Joe Louis to Lennox Lewis or Wladimir Klitschko. Who hit harder? Compare the left hook of Dempsey to Mike Tyson. Baer's right vs Wilder's etc. Compare punchers with punchers. The size difference will show up. Think of all the great punchers that weighed 175-185 lbs. And compare them to punchers that weighed 220-230 lbs. Holyfield beat Valuev. But Holyfield also got stopped by a blown up middleweight. This was 5 years before the Valuev fight.
I think size is more of an issue, to a point, within a fighters psyche. I think thats why you saw a lot of catchweights fights in the old days that werent mismatches. Fighters just didnt think in those terms back then like they do now. Today a few pounds is a big deal when at one time that would have been a non issue. Its probably a byproduct of all these stupid weight divisions.
Satterfield also knocked Williams cold. Keep in mind that Satterfield was 176 pounds in that fight. Louis right hand could have matched Lewis right. Louis sent the Lennox Lewis sized Buddy Baer spinning to the canvas with a right. I mean, if a modern HW made a 230-250 pound top rated contender spin to the canvas with a single right or left hook, we'd be worshipping his punching power.
I know Satterfield knocked Williams out. Quarry KO'd Shavers in the 1st round. And Quarry wasn't even a big puncher like Satterfield. Quality of chin played a big role in these fights. Satterfield did not hit as hard as Williams IMO. Williams had a suspect chin and he was only 20 at the time. Satterfield was 24 lbs lighter than Williams. But Satterfield was a lot more experienced than Williams. Williams was a last minute replacement. Louis gave Baer a beating before he knocked him out. Lewis dropped Grant 3 times in the opening round. Grant was 250 lbs and a better fighter than Buddy. Louis' right hand does not compare to Lennox.
This seems completely obvious. Yes, depending on the individual fighter, smaller fighters can hypothetically beat larger men. Are you sure this is really your only point?
No way a modern welterweight would get in the ring with a big middle weight like LaMotta on fight night with him weighing in the Welter limit and LaMotta 160.
I would go so far as to say that Louis could have dropped Grant 3 times in the opening round. The point is, just because a fighter is bigger it doesn't necessarily follow that he hits harder. A monster 185 lbs puncher COULD hit harder than some 230 lbs fighters. Not all but some. A very good 190 pounder COULD beat some bigger men. They aren't doomed because they weigh less.
My point is what I stated. I promise you that if Buster Mathis were were fighting today, there'd be someone saying that it's no way that Frazier or Marciano or Dempsey or even perhaps Louis, hits as hard as a 250 pound monster like Mathis.
Who disagrees with this? Do you really think there are people who don’t realize that a very good 190 pounder COULD beat some bigger men??
Fighters with physica advantages are tougher to beat. They are generally stronger, tougher to reach and many times hit harder. That's why beating good boxer who's bigger than you is always a big accomplishement. It doesn't mean that smaller fighter is always lost or that smaller fighter can't have better chin/punching power. The history of boxing shows so many examples of smaller fighter beating great bigger fighter that it's reasonable to assume that it's possible. Size matters but only up to a point.