Oda also made Dragon such a bum this arc. Like there's no reason for Dragon to be such a weakling when he has Garp as his daddy in the marines.
When Kuzan first joined marines, he already mastered everything marines can teach.
When Akainu and Kizaru first joined, they already became known as monster rookies
Starting to doubt that Dragon is even near Admiral level. Sounds like he is only above mere yonko level.