if people had seen his fight with Joshua, they could see he gassed by round 5. Dubois is cool. I would say he is like nr.3 (nr.2 if Fury has actually retired) right now. I put Dubois higher than Wilder and Joshua.
Dubois is still clearly a top heavyweight contender and can still be in some very interesting fights, with Bakole, Parker, Wardley, Kabayel, Ajagba, Chisora, and several others. It's unfair to say he quit against Usyk, he actually gave a fairly good account of himself against an ATG heavyweight. He showed plenty of heart and stamina against the relentless Miller.
It's not overly complicated why Dubois lost ( twice) to Usyk. Usyk is the better man. Skill wise and mental fortitude. Levels.
Glad you've finally realized the truth. Seriously though, you need to do some film study. A supremely in shape guy like Dubois isn't gassed by the 3rd round because he's landing all his punches and having major success. This dude went much farther in fights with bigger guys while getting absolutely blasted repeatedly. Didn't have any problems with his stamina or heart and went on to win those fights. Yet against old man Usyk he was blowing out his ass after a few rounds and done early in the 5th. I wonder why.
Because there’s not a split second of rest against Usyk. Extremely exhausting to deal with, mentally and physically.
Usyk is probably the best defensive HW boxer of all time, with the highest ring IQ too. Usyk can adapt his style to whomever he's facing. All of the names you mentioned there got knocked down or knocked out throughout their careers. Foreman got dropped and lost to Jimmy Young, and his fight vs Lyle did not display good defensive skills either. Tyson's prime lasted how long, around 1-2 years? And then he got exposed by Buster Douglas at 23 years of age. Holyfield blocked a lot of punches with his head and lost 10 times during his career. Ali got dropped by smaller guys like Henry Cooper and struggled vs southpaws. He relied on reflexes to evade punches rather than technical skills, which forced him to endure some rough wars. All of those guys are goat's, but technically they're not on the same level as Usyk (imo). I don't think there's any other sport/combat sport where nostalgia is as strong as in boxing. A lot of fans will still tell you Joe Louis or Jersey Joe Walcott would KO Zhilei Zhang and Anthony Joshua.