Sanji said he will be the man the Marines will fear the most.
Is that also a statement you agree with?
Because Sanji said it so it must therefore be true?
That's not how things work, Nik tan. The only characters whose declarations end up true are Luffy and ironically Usopp, but only for gags.
Actually, yes. I do agree with that statement.
The issue is that ZKK doesnt rely on one Zoro's statement, there is far more to it.
It should be known to everyone by now. If not, there is still that collection thread that listed tens and tens of connections between Zoro and Kaido and why ZKK should have happened.
Zoro's own statement, Zoro inheriting Enma and Oden's will of slaying Kaido as well as Kaido being World's Strongest that nobody else managed to kill were plenty of build-up for ZKK but as I said, there is countless more.