Some people have gender dysphoria. It is a real condition. It isn't uncommon for someone with this disorder to end their own life.

I don't deny that. Neither does the professor. And he doesn't advocate acknowledging people from their chromosomal gender (ie. transwomen are 'she' and not 'he' and it is natural for anyone to do so)

The debate is fundamentally about freedom of speech and the validity of individualist outcome dependent justifications. Why should someone being uncomfortable about a pronoun be the concern of others? What if someone is negatively psychologically affected by having to alter their speech at the whims of another?

A choice of non-binary pronoun is just as fluid as their concept of gender and can be switched at any time. The idea of masculine and feminine, and gender isn't just about individual choice. It's about perception. If someone thins they are 'non-binary' and most people recognize them as a man they are only non-binary by self-definition. We can't control how others perceive us. Desiring that is part of the problem for people developing self-esteem and mental health regarding their gender identity. Problems of acceptance and becoming individuated and comfortable with oneself is something everyone goes through. Language we share and changes happen organically and should not be state enforced.

The individualist outcome dependent justification is flawed. There's no proven reason why a pronoun would make a difference in trans acceptance; it just may do the opposite.

To make it a legal violation to not call someone by their pronoun of choice is contrary to free speech.