Their whole philosophy hinges on the first point: "Sex is biological, what a child has been assigned at birth. It's not always correct and doesn't match with gender identity."

Not only is it opinion, it doesn't make any sense unless you accept the framework that gender identity exists and that someone's mental state is somehow more "correct" than the physical reality everyone can see. An adult needs to rationalize this degeneracy with several layers of bullshit ("the latest academic research tells us there are 37 genders!") but to a child it's religious dogma they absorb without question. As they get older their teachers will encourage peer-pressure or bullying to keep them from asking too many questions.