It's fits the narrative perfective IMO, because Luffy can then go on to beat BB/Shanks whomever Oda would have decided next. I get what Oda was trying to do with have everyone fight Kaido to an extent to weaken him then have Luffy keep going in for the win to help justify going that route, the issue is it makes situations like this predictable, and gives Luffy the character trajectory of other main characters like Naruto, Ichigo, etc.
Im on the same boat as you in the path for Luffy to become the strongest which is why the 3 v 1 was have been a perfect step to the next level.