A real fight Luffy vs Kizaru (not the stupid game of tag that was the first round) would be completely different than Luffy vs Kaido. Kizaru can't eat as many hits as Kaido did but he doesn't need to.
Wano was all about defeating durability freaks (Kaido, Big Mom) the following arcs will be about other challenges.
I still think Luffy might have to improve his COO even further or develop some new type of speed based attacks in G5 to beat Kizaru.