The J80 is a sprit boat, and therefore will use assymetrical
spinnakers. On the J22 you will learn the ins and outs of
rigging and handling a conventional symmetrical
spinnaker.
Good foredeck skills with a symmetrical
spinnaker will translate to more rides on a wider variety of boats. Good bowmen/women are in demand.
Sailing upwind, the skills learned will be comparable, and the difference in size will make minimal difference to what you will learn.