I ask because one of the biggest arguments was that the Straw Hats don't kill, and Luffy is THE Straw Hat. If this is the ending, that means Luffy made his one and likely only kill without any sort of intention, fanfare, or certainty. Weird way to write a story.
The last time Goku killed a major antagonist, King Piccolo, he was super pissed about everything that went down and still tried to refrain until he was pushed. He went from killing if it made sense to killing if necessary, to training with Kami and growing up to actively avoid killing. Shallow series, but extremely popular and probably the biggest influence on Oda.
So then he makes a series where pretty much no one dies and Luffy never kills, except now he accidentally kills Kaido while goofing around, and it means nothing for his character? I dunno. Even weirder if this is despite dozens of other characters, Zoro included, actually aiming to kill Kaido.