What if your preferred pronoun triggers someone else?
What's to stop me from demanding that people call me "hitlerdidnothingwrongiloverape" as my preferred pronoun? Yeah, it's a ridiculous pronoun, but the law makes no distinction between any preferred pronouns. If my boss refuses to use that pronoun, are they creating a hostile work environment?
This professor has an issue with demanding that someone use a made-up pronoun to address them. He has no issue with referring to an MtF transgender person as "she" and "her" (and vice versa).