I'll be brutally honest with you: I have _learned_ #English. I know. Shame. 🎒
Anyway. I've been taught of grammar, including #pronoun's. Not me, not even any teachers I know is aware of the existence of "#they" (apart the ones I've informed about it).
That's what I meant. He is taught, She is as well, and the most obviously logical way is to list them all (like "he, she or it" when you don't know even that). I usually use s/he, since I'm a lazy geek, and that form is ancient.