Why isn’t Steven Class Z?

[MintyBoi1]

I’m looking at Steven Universe’s profile and I’m confused why he isn’t Class Z in Pink/Monster form. It notes that he could break out of Lapis’ binds which are Class Z and he reasonably should scale above all other gems due to feats of beating all of the diamonds who individually overpower Lapis.

 

[Therefir]

That's because Lapis' profile doesn't specify that she only has that rating when holding all oceans on Earth