Meh, at the end of the day Luffy did surpass Katakuri. And even Katakuri could be kind of an exception like Kizaru where Luffy didnt destroy his dream. But Kaido is like Doffy, Croco, Buggy etc where he knocked them into the sky and destroyed their dreams, which Oda says is worse then death for a pirate. It just doesn't make sense for Wano to be as long as it did without Luffy surpassing Kaido, especially when you consider how important it was narratively for Luffy to become a Yonko etc. Especially when you have characters in the story saying Luffy is the one who beat Kaido, while no one ever really credits Zoro or Yamato. I think its probably simple how Oda views it.