I don’t know about hitting as hard as Beterbiev but honestly Bivins would even rule 175lbs for a long time today undisputed.
As someone whose done extensive research on this topic Bivins HW title had recognition in 48 states and the LHW titles were uncontested except when Bivins was about to move up to HW and they named Marshall. The duration LHW title was decided by a tournament with 4 of the top 10. Bivins v Charles was the SF of said tournament. Also duration just means interim. Its a proto interim title.
Greb did win a real title and he didn't get knocked down 11 times in his 2 title fights. Think he was 2-1 or 2-1-1 or something like that.
Only at Middleweight. He basically won his era's equivalent of the WBO NABO belt at LHW, who nobody in their right mind considers a real world title. So he was essentially beltless. And his record in said ''title fights'' was 2-2, which is also far from GOAT worthy on the surface. Need I really remind you again that 8 of those KDs were in a fight where he had a severe back injury ? Against a man that was considered a hellish puncher, one who he would go on to absolutely thrash in round 6 and round 2 of their rematches ? Your clinging on to those 2 fights has gotten ridiculous at this point. Nobody cares about them and nobody ever will, because they are unimportant. What is important is that Charles beat what would otherwise be the GOAT LHW 3 times, absolutely thrashed Marshall both times when both were healthy, and proved his utter superiority to Bivins when both were fully developed physically and at their peak. The rest is just negligible nonsense and cherry picked stats.
The majors belts of the 20's were the NBA and NYSAC titles, the ABA was just a north American title, just like the WBO NABO. They are of the same worth.
This is revisionism. All sanctioning bodies at this time were national in nature. NBA was national you know hence the "National". And NYSAC was and is a state agency. The WBO NABO isn't even the NABF or USBA.
Semantics. The NBA and NYSAC were the only titles that were considered ''world'' titles. The ABA titles were not. Hence why nobody considers Greb a LHW world champion. It is you who is committing revisionism here by considering it a major title.
Boxing has advanced so much since the 1940/50's this isn't even fair. A Joe Smith match-up would be more fair for Ezz.
Tough fight for both, not easy to counter a fast and skilled outboxer like Bivol and not easy to hit a fighter like Charles without being counter. In a match between one of the best light heavyweight ever and the best light heavyweight in history I say Charles by close decision. The Ring IQ, the versatility and the difense of the Cincinnati Cobra would have been decisive, he would have imposed a fight from inside to Bivol and would have placed the best shots, even if the Russian would have had his moments.