You really want a list of HW's who I think could beat Fury ATM? That would be speculation, because he seems to be more focused on tune-up fights and fake retirements. We'll see if he fights someone on the level or Kabayel or Wardley.
You're right. "Come back from a loss" is an expression where I'm from. I can't even imagine what the word "retired" means where Fury is from. It's become Fury's version of "inconceivable"
Usyk's best wins for me is Briedis (but that is CW). I don't like to include his CW achievements in his HW resume, BUT winning a tournament against a number of prime opponents, taking zeros along the way, is his best career achievement. At HW, I think it's a tricky one. On the one hand, he beat Joshua coming off wins over Ruiz and Pulev (but Joshua's mystique was already gone). Still that was a great win for Usyk. On the other hand, he beat Fury coming off wins over Chisora and Ngannou (and that tells it's own story). Then we have Dubois 2 coming off the best run of form of the three (but he'd already beaten him with ease the first time). Hard to separate them really, not worth making a strong claim about X is the best win. I think the general achievement of beating those three is more than the sum of its parts
Opetaia isn't a heavyweight, Kabayel is a maybe because he doesn't have many high level wins himself, Wardley is too basic. EDIT: Fury is absolutely Usyk's best win at heavyweight
Wallin almost beat Fury. The referee was generous to Fury, allowing the fight to continue with that cut. And Fury was tottering around like a drunk in the 12th round. Ngannou arguably deserved a decision win against Fury. Those look like very close calls, almost ruined the Wilder 2, and the Usyk 1 plans. And that was a younger Fury. Makhmudov isn't a whole level below those two. I think it would be wise for Fury's promoters to guarantee Makhmudov loses, IF they are looking to set up certain future fights for Fury.
How is Opetaia not being a heavyweight relevant? He would be favored over many heavyweights and Fury is not a big puncher so the weight jump wouldn't be an issue.
Wallin tried to win via fouling on Fury's cut by blatantly rubbing his glove on it. Fury still soundly outboxed him. Ngannou Fury clearly didn't train for, but he still won. His next fight he came in form and gave a very competitive display against Usyk. "Almost" still means wallin and Ngannou lost. No revisionist history here.
Are you serious? It's not relevant because he's not even fighting in the division. He's a non factor and it's not even proven he'd be able to handle the weight and reach disadvantage. When he actually makes the transition you can start bringing him up. Until then he's still a cruiserweight.