Sure it is:
If I harass you because i don't like you personally, that's a different situation than if I was harassing you because you're a guy. Motive matters in most crime. Same way that killing enemy civilians is a crime, while killing enemy civilians for specific reasons regarding inherent traits is genocide. (Overblown example, but it's 5am and nothing as clear cut was coming to mind)
While you're entitled to your personal opinion on whether or not gender, sexual, or racial harassment should be treated differently than personal harassment, it fits well within the legal purview of the Canadian justice system.
To build off of this, a lot of you know that I'm a black man.
Because I'm a black man, certain things have a deep seeded meaning when you use it with me. Although I'm a male, calling me a 'boy' after I reached my adult years is tantamount to racism because of the history of black people in this culture. Even adults back then were denied the respect of being referred to by adult nomenclature due to the 'inherent' juvenile nature of the slaves. And plainly, the slaver owners saw no need to respect them.
So while I could debate on gender being inherent (anatomy and physiology is blatantly inherent, but the brain and its wiring can yield a myriad of different results that are not just visible to the naked eye), pronouns aren't. Because Pronouns are a made up way of communicating with the limited knowledge of what we know. If we don't know something, we just don't say "We don't have a word for it, so everyone pretend that it doesn't exist". We go about naming it in attempts to understand it.
We can easily expand our language as we've done countless times before. And hell, using '
they' has been standard practice when the gender is unknown since the 14th century at least. The issue has never been grammar. At the least, it's people who are just this side of lazy who don't want to do anything extra for other people. And at most, it's an attempt to delegitimize a group of our fellow humans because certain people can't accept things beyond what they are comfortable with.