Yasuo's windwall blocks Lulu polymorph?

In a recent game I tried to polymorph Yasuo through his windwall and my ability just went on cooldown. I'm guess its because her polymorph is an invisible projectile?

Yasuo's windwall should be nerfed so that fight changing abilities aren't completely ignored. For example ultimates, cough Nami cough or abilities like Lulu's W were it literally turns a hated assassin into a squirrel.

-This is coming from a Yasuo main so its not just another person on the bandwagon of Yasuo hate.