If Wlad, Vitali, and Lewis had been limited to the traditional training methods available in the 1960s (we will assume not only that they can't use weights, but also that they're barred from chemical assistance as well) would they have ended up as significantly larger men than Ernie Terrell?
They were some big guys in general bone structure wise. Physically they were monsters. I think they could benefit from your idea especially if they’re put in the 60s they’d still be the biggest guys around just this time they’d have a lot better stamina. My worry would be Wlad losing strength might make his clinching an issue.
Also I’ve always been curious why people think the 6ft5 guys would look like Ernie as if there’s one stock build lmao. My Pa is 6ft2 and broad like Ali my friends Pa is 5ft11 and rake thin. “If Lewis was around back then he’d be 200lbs tops and a stick like Terell those taller guys wouldn’t be able to fill out” Guess Ali, Foreman and Norton got lucky by being 2 inches or so shorter or else they’d somehow be built like an ostrich and 20lbs lighter.
Terrell was 6'6", wasn't he? Terrell actually wasn't rake thin. He was skinny, but he looked 60s-boxing-skinny to me. Not too different from most of the other guys. Foreman was a naturally beefier guy, so an outlier by his era's standards. Norton you're pretty sure was on steroids. There are more 6'2" to 6'3" guys than there are 6'6" guys, so I'd expect the shorter guys to have among their ranks naturally bigger men. If you're looking for a burly guy Terrell's height, you have a smaller selection to pick from. Meanwhile, Lewis and the Klitschkos had an incentive (and, in Vitali's case, confirmed access to steroids) to get larger when they were younger. I'd expect them to make use of that if they could. So I'm not sure that their weights in the 2000s are their "natural" ones.
Oh they’d definitely be lighter. Per average taller guys are skinnier but I think that has more to do with food requirements then anything. Wlad, Vitali and Lennoxs natural size is apparent even if the only thing you had access to was there skeleton you’d know. If they eat to meet the requirements to grow then they will which I imagine is a lot being a high level boxer, 6ft6 and not being able to use weights really isn’t the best recipe for size. Throw in some weights you increase your chances and some roids you’re on easy street.
While they would not have been as big as they were, you clearly see fighters from the past who were similarly built. They just happened to lack all skill and athleticism required of elite fighters, and were basically used as a cannon fodder. Isuspect they would have all fought closer to 230 lbs.
Yes they would have likely averaged around 230 lean. Again they may well have used or not. And each guy may be different re: how much he used when-if they did. But Lewis before Manny boxed in the 220's, say a 227 would be commonplace. Likely sithout efforts to bulk up-regardless of naturally or not-he would have only added fat over time, not muscle. Vitali cheated at least a little, but given his height he could have been a little heavier than Lewis or his Brother. But I recall being no more than Ali at 212, at 6' 6" this is thinner than the other 3 would be likely to be naturally.
Even without steroids, Lewis and the Klitschkos definitely weight trained, as I think you note. Since 60s fighters didn't (usually), they might be smaller even without getting into the chemical issue.