Yes.
So he should fight Big Mom?
Wrong. Big Mom is the strongest swordman currently present in Wano.
However, I don't see you or much people pushing for Zoro vs Big Mom. A bit weird.
Sure, that's assuming we are following the general structure for a villain group. A leader, 2 (maybe 3) strong subordinates. And a bunch of lesser subordinates.
That's also assuming the ones doing the fighting are the straw hats.
These two things are already not the case.
Here, we have 2 leaders, 2 remaining strong subordinates + (F6) vs 6 supernovas, Scabbards (before they got defeated), and Marco.
This isn't like your conventional arc, the straw hats don't lineup perfectly against the opponents.
So using the old recipe for matchups is a bit useless.