There were plenty of skilled superheavys in the 1914-1946 period. For whatever reason from 1946-1966ish there was a very steep dropoff there. They came up with the Superheavyweight belt for Buster Mathis. This was not first time that division was tried. It was also piloted in the 1930s. Now not a lot of fighters weighed 230 back in the day even if they could carry it. But even so you still have Carl Morris, Godfrey, Carnera, Buddy Baer and Abe Simon off the top of my head. Something about Baer and Abe Simon is their whole career was their early 20s. While Mathis also retired young he had a full 5 years on those guys. Baer and Simon really could have been something special.
The guys mentioned Abe Simon Carnera etc were total stiffs. So yes if your cutoff is 230 then yes Buster first with athleticism and skill at that level. However if you look below 230 though small by today’s standard Liston should also be considered. Though a bit under 6 1 he was a solid muscular 215 with an 84 inch reach. When he fought anyone other than Ali he looked like a super heavyweight fighting a small heavyweight. He was that much stronger and more powerful than anyone else until George Foreman. Though not in his class as a fighter Jim Jeffries size might be considered and he of course did accomplish quite a bit so was an outstanding fighter in his day.
Buster Mathis was an obese HW. Frame-wise Riddick Bowe was probably the first SHW whose skillset went beyond a good jab.
