Nope, never saw much of usyk. After big win in recent years, people are always apt to say, "he's one of the greats" or "he's invincible" or "he's the best yadayada". He's the best heavyweight right now, why can't that be enough?
Who beats him? Well, just like who beats anyone, whoever can land either more or powerful enough a punch. Usyk has solid defense, hard to hit clean, southpaw who knows how to maximize the stance. Let's see someone punish him to the body, maybe try to bring those hands down, he has a good chin but let's see it checked, lets see him have to fight out of a hole. Not everyone can turn things round when they are losing, has he done that? Some awesome fighters couldn't and it counts against them. or..., he's 38, he can just retire.
Great analysis: