Wlad was 24 when he beat a very good champion in Chris Byrd for his first title, not some St Louis mug with 0 genuine wins of any note.
Joshua is 26 years old wtf are you talking about him not being prime yet? This is as good as he'll ever be.
Let's not get too ahead of ourselves. Joshua doesn't really deal with the jab very well. Dillian Whyte exposed that out of him. Nobody has taken away AJ's favorite weapons that a good boxer would be able to do. Sure if Wlad or anybody lets him just show those counters in he right range you're going out.