Everyone who says "gender is a construct" is putting the cart before the horse. That construct didn't develop arbitrarily or in a vacuum, we arrived at it through millions of years of evolution. All mammals have two sexes (anything else is a mutation - where would we be without some good mutations?), and their primary, biological imperative is to make more mammals - to propagate the species. Anything else is just gravy. Ergo, any construct stems from biological sex. Trans goes against all things in nature. You can say you're a woman trapped in a man's body all day, but it doesn't make it a fact. You have a disorder and transitioning is simply the only treatment for that. Trans people will never be the sex they want to be (notice none of them want to transition to null or a sex that doesn't exist - it's M or F), they will only ever be an altered version of their biological sex to treat their dysphoria. What's this guy's PhD in, anyway? I've seen a few Ian Copeland's out there when you google him.