Why would removing the seasoning improve the performance of cast iron on an induction stove?
Polymerised oil in no way interferes with a magnetic field. The cast iron heats up from the inside out, just the same.
Or did you just do it to keep your stovetop clean?
My griddle, due to the edge on it, doesn’t sit flush on my stove, there’s about half a centimeter air gap. Yet, because induction is just a powerful switching magnetic field, it heats up just the same. It just needs to be close enough to the electromagnet below the stove surface.