ZKK was reaching, since Oda would not have had the balls to have one of our protagonists kill an antagonist in such a graphic way, yet Zoro did more in this arc than any Zoro hater would've anticipated (stopping Hakai and scarring Kaido pre power up and with a crushed skeleton).
ZKK was probably a meme for most of the people who proposed ZKK, engagement bait so to speak. Gun to their heads, probably no one would've held onto it.