Since the beginning of the series, Oda has been extremely reluctant to kill of characters, be it Luffy’s major rivals and antagonists, or even minor side characters who contribute little to the story as a whole.
In one of the first volumes of One Piece, Oda explained why Luffy does not kill his enemies: Luffy shatters the beliefs of his enemies by defeating them. For them to suffer defeat and to have their beiefs destroyed is as bad as death. Killing their bodies is beside the point.
Kaido is certainly an example of this. The man does not care about his life in the slightest. In fact, he actually wants to die. Would killing Kaido follow Luffy’s trend of destroying his opponent’s beliefs?
Kaido starts a war on a whim because he’s tired of living and ostensibly would like a final grand exit from this world, a glorious death in combat with a worthy opponent. Despite his 100 hostage-taking ways, Kaido apparently does care somewhat about fighting fairly with a worthy opponent given that he killed Kurozumi Higurashi for backstabbing Oden. You could argue that Kaido himself took advantage of the distraction to strike Oden down, or that his character is just a mishmash of poorly integrated tropes and stereotypes. You could also argue that killing Kaido would be the first time in the series that Luffy and co actually granted the enemy’s greatest wish. I’m not disagreeing with any of this, but I think the difficulties with killing Kaido extend far beyond that.
Oda does not like killing characters. Other than the very obvious example of Pell, we have King Baum, Charlotte Moscato and Pound, three characters who were shown killed/implied to have been slain during Whole Cake Island but later reappeared alive and (fairly) well.
Whatever Oda’s reasons may be for resurrecting even the most inconsequential of characters like Moscato, Oda does not like character death.
Remember when Bellemere was shot point blank in the head in front of her children?
Can you imagine a scene like this being drawn in 2021 One Piece? Only two crew members are confirmed killers, that being Zoro and Nico Robin. Neither of them have killed on-panel, with their previous murders mostly glossed over by the manga. Will Oda ever allow Luffy to kill or Zoro to finally ending a life on-panel in a glorious double spread? Will the job fall to Killer or Law, two individuals with far less reservations about killing? This is extremely unlikely given how Straw Hat-centric the manga is.
What do you guys think? Would Kaido’s dreams be shattered if he dies? Does Oda actually have it in him to make the happy-go-lucky, cutesy mascot loving, family friendly post-timeskip Straw Hats into murderers? How will Oda solve the killing problem?