My favorite 1v1 in the series:
Kaido vs Luffy (and Zoro and Killer and Kid and Law and Kinemon and Kiku and Izou and Asura and Kawamatsu and Neku and Inu and Denjiro and Yamato and Momo).
Great 1v1.
Luffy can't beat Kaido in a 1v1 still at a battle starting from full health. Gear 5 runs out before he can beat him, IMO, and Bajrang Gun only hit because Kaido refused to dodge it.
Kizaru vs Luffy is showing us what a lot of Luffy fans really didn't want to imagine: that Luffy is way closer to Kid in power level than Shanks. Until Luffy gets his cooldowns under control, he can't 1v1 top tiers, because he can't beat them fast enough in Gear 5 before it runs out.
Name another top tier that has cooldowns for their strongest techniques?
Imagine if Shanks attacked Kid, then sat down and was like "okay, give me like 10 seconds to recover, that was a lot of Haki." He would get clowned so hard by the fanbase.
Kizaru is such an intelligent fighter, he's making Luffy waste a lot of time just chasing him.