If we include the WBA's regular title I'd say Trevor Bryan right now is a good shout for worst ever. I honestly think Charles Martin would beat him based off of his defence vs Stiverne.
They are better than Wilder. Both would UD his useless ass. They are just boring, not bad. Wilder is exciting but bad. At least Valuev had a jab. Wilder doesn't even know what a jab is. Look at the video when Lewis tried to show him how to throw a jab. Valuev would probably even KO the windmills after he tries to drop Nikolay and gasses badly.
The one that springs to mind for me is Buster Douglas. He undeniably won it empatheticily against all odds and then lost it in his first and only defence against Holyfield very easily. Some will say he only defended it for the paycheck and made no real effort in his defence. Certainly not the same huge effort and belief he put into winning it. In that vein you could also have Andy Ruiz as a poor champion for similar reasons. He made no real effort once he had the belt as regards training and conditioning.
Martin doesn't even have a title defence so if we aren't following my criteria. He must be the absolute worst.
Trevor Bryan doesn't really have a major title but its a title i suppose so he counts here. I forget about Bruce Seldon too. Andy Ruiz i think could be something in the future its just he needs to keep his fitness in check.
It happens to a lot of fighters. not even just champs. I think Douglas and Ruiz Jr could fit the bill but i think Douglas more so.
It does say a lot because like, from what i read he was never very talented at Boxing at any point. He started out playing Water Polo LMAO. His promoters never gave him hard fights early in his career because they saw him as a clown really. like a spectacle more than a fighter but eventually he somehow got title fights and won through dubious judges choices or just fighting other bad champs (I.E. John Ruiz)
Martin could beat him now tbh. Martin was a pretty ass champ but he also never had time to be champ lmao. And he has at least a few skills compared to Bryan.
the Aussie is Lucas Browne i think and yeah hes pretty bad. His win over Chagaev was when Chagaev was shot.
I always liked Parker but honestly i could see him losing to Valuev on Judges. VS Hughie Fury he didn't look super good in my opinion. He also hasn't fought the best competition either, I think Junior Fa gave him some problems.