Don't get me wrong, they are good, but admirals never got hurt, yet yonkous get humiliated every chance they get. Laidou with scabbards, big mom kicked down by king and by jimbei, shankas lost his arm to lord of the coast, wb in war.
luffy fell from 25,000 meters onto his ship(zunisha) does that make luffy<kaido?
Just because yonko were hurt doesn't mean they are weak, we've seen how terrifyingly strong they are