The interesting thing about pronouns is that the only pronoun used to directly address someone is not gendered, it’s “you”. So it is not actually possible to directly misgender someone.
The words “he” and “she” aren’t slurs. Comparison to the word “cuck” don’t make any sense. Should a job require someone to use preferred pronouns? Well I go back to what I was discussing about free association, if they want to sure, if they don’t that’s OK too, but going after a workplace without such a requirement takes things a bit farther than just wanting to be left alone.
And as far as teachers, I actually don’t think kids should be forced to go to school, so that would really be a different issue. If they’re old enough to determine their gender they’re certainly old enough to educate themselves or determine if they even want an education.