Defeated Luffy three times.
Fought and defeated the Scabbards.
Fought against five Supernovas.
Fourth time defeating Luffy and this time actually killing him.
At this point I don't know how anyone can say that Kaido didn't live up to his hype, this man is an absolute beast and imo Oda did a great job portraying how much of a monster Kaido is in terms of power level.