Seems like Oda's answer for Zoro in post-TS are opponents with a form of complete invulnerability.

It's crazy what he has to pull to keep Zoro in check... "Normal" people cant keep Zoro busy more than 5 minutes.
First came Pica. You can attack his golem all you want but he is invulnerable as long as you dont corner his real body.
Then came Kaido with 2nd best defense in the world, paired with Big Mom to stop Zoro with Hakai.
Then came the invincible King with the best defense in the world.
Shiryu is also invincible as long as you cant cut Nothing.
I dont know what Kizaru and Gandhi will have but I wouldnt be surprised if they also have some form of invincibility.
Kizaru might pull some kind of light reflection with super speed making it hard to hit the real body. No idea what Gandhi will do.
And finally Mihawk, another form of invulnerability, cutting through Yoru aint happening until he pulls what nobody else has - Kokuto.
It's crazy what's necessary to stop Zoro.