Firstly, do you agree with Peterson this bill forms an unprecedented and new challenge to free speech in Canada?
I don't know. I'm not a lawyer. Peterson's explanation of why it does is compelling but perhaps he will be shown to be mistaken. If it does coerce others to use made-up pronouns then it is a very bad law and should be opposed by everybody who cares about free speech. Even those who think that made-up pronouns are charmingly whimsical.
trans people should be a protected category, i.e. that you are not allowed to fire a fireman for coming out women similar to how you should not be allowed to fire him if he converts to Christianity?
I'm not sure if I'm on the same page with you about that. Converting to christianity demonstrates poor judgement but it probably doesn't interfere with a person's suitability to do most jobs. Insisting on turning up for work as a hotel receptionist in a dress and a beard probably would. That is why it is a badly formed law. "Gender expression" can be interpreted to mean absolutely anything.