Lets see
If Zoro wasn't there
Hiyori would have died.
Apoo would have killed luffy
Kaido would have killed Luffy
King would have killed sanji
Kaido would have killed every other samurai
Queens virus would have killed everyone including chopper Drake Hyogoro and bunch of samurai
All of that is very definition of moving the plot.
Defeating King kaidos right hand man is literally moving the plot because anyone else who stands a chance was busy.
Same goes for
Yamato - stall kaido otherwise Kaido kills everyone
Kid & Law - fight BM otherwise she kills everyone
The point is Zoro role in Wano is so bland and ordinary. He is supposed to do something special due to his multiple plotlines like Ebisu, Ryuma, Shitmosuki, Black blade, nidai, samurais, and his big talks. Wano is the land of Samurai after all.
In the end, he is just a fighter who helps save captain and fight the third strongest villian. That's it. No story around him like Sanji in WCI or Law in Dressora.
As now Zoro is my only reason to read OP, time to quit for me