Well how highly you think of Zoro will only be settled from Zoro vs King. A clean 1v1 with the strongest swordsman
Remember Drama. Even now, we are still building drama. Oda gave a little pay off their with Zoro's frustration leading to the one shot of Apoo. But clearly this isn't the final fight for Zoro and so we are still building drama.
When Zoro cuts Kaido, that will be another pay off for the drama around Emma that has also been building. And of course that would mean Zoro is stronger than all the scabbards.
And then when Zoro fights King and wins extreme Diff. That will be the end of the drama for Zoro this arc and THAT'S WHEN you will have to judge your expectations against the reality.
It's unfortunately just a rule. Oda cannot actually show max effort until the point of maximum drama.