Oda never thought of adcoc until after Oden flashbacks
That's why splitting the sky is now when top tiers use adcoc in a clash
You can see Kata has thick zigzag CoC haki trails from his attacks but that's not it.
Oda will grant adCoC to anyone at this point
Zoro using adcoc without knowing he had CoC and can't even control basic Coc should end this debate "adCoC is hard to have"
Or else Doffy, Ace , Kata etc...who Mastered basic CoC would be using it
Especially Katakuri who is a haki master.
Translation: you have a problem with CoC/ACoC because it goes against your headcannon and it makes you look foolish since you spend a lot of time hyping up CoC.
Luffy went directly from not being able to use flowing CoA haki to using internal destruction haki. A power he didn't even know existed.
Zoro knew about CoC which is a power you can't learn. If you have it or you don't. Zoro jist didn't know he had it. He has used flowing haki since pre TS. Kaido the one who told Zoro he had it and Zoro just use flowing haki to CoC.
Just because you can use one type of haki and at one level doesn't mean you can use it at all levels.