1. Being Equal doesn't mean it's during each & every Moment of Story, nowhere does it say They Progress similarly & at same Rate
2. Being Equal as Wings doesn't mean They share every other Ceiling
Wings + Rayleigh/Gaban + Every First Mate & Second Mate Comparison shows that:
When Zoro is at Level of Pirate King Right Hand Man, He will be Equal to Sanji when He reaches Level of Pirate King Left Hand Man,
It doesn't mean that is where Zoro Stops, nor does it mean They will Progress & reach Similar Levels Simultaneously,
Those who think Sanji's Ceiling is same as Zoro's is like those who still think Roger is Luffy's Ceiling lol