That means it would've been even easier for Zoro to unlock CoC with proper guidance. All it takes for Sanji is to tell him "don't doubt yourself" and he awakens it in an hour. Zoro was grinding for 2 years wanting to get stronger and Mihawk only told him to remember for the future.
Of course CoC is important, I am not denying it. My point is, that WSS title is not simply = having the strongest CoC of all, but being the strongest in a particular fighting style which obviously includes CoC. If Kaido switches his club for a Meito and mimics his Thunder Bagua attacks with it, him beating Mihawk won't just turn him into the WSS.
That's why you hear every dedicated swordsman, be it Zoro, be it his master Koshiro or the Wano samurai talking about cutting what a swordsman is measured up to. No one ever said using sword strikes that resemble a cannon ball and Hammer (Xebec) being testament of great swordskill.