The spinners were just too big and that made the packaging cumbersome. This means awkward shelf stocking and shipping in the long term. They also do not has as much of an impulse buy as the spinners because of the size.
Then you have to consider that the air launching function may have made parents wary of getting something that could be sent spinning in a child's face.
Lastly, with such small sets in Ninjago anyways, the incentive of a gimmick introduced randomly in a wave lessens since often one can get a set with a more substantial vehicle or setpiece plus a few minifigures.