Usyk gets a time machine, does he clear the top level of every era and go undefeated

If Usyk turned pro pre-the creation of the CW division he wouldn't need to bulk up to fight literal giants who were way bigger, heavier and more powerful and if he were to be facing a genuine SHW sized giant very occasionally he wouldn't be facing the athletic, skilled, and fast for their size SHW sized giants of today he would generally be facing low skill, slow and unathletic Frankenstein's monsters who didn't even know how to use their range

And a pre-invention of the CW division Usyk would be the razor sharp, mongoose agility and reflexes, higher output and more accurate Usyk we saw in the WSB and CW division and if you want to argue that version had a (shock horror) close fight vs Briedis and lost a few rounds in some of his other fights at CW, we have to fact in that he's far from a one-trick pony and is a versatile fighter who chose to fight in certain styles for certain fights and when he wants to be much more elusive and difficult to pin down he can box beautifully when chooses to do so