@oldkinghamlet @theleftistlawyer she/he/it does not "apply to everyone" as one person you call she, another person you call he, another person you call it, etc; you do not refer to the same people these ways; that was the point, its like names in that you might call one person john, another marry, another mike-
and its also impossible to know someones pronouns just by looking at them either; you can only make a guess to them, based on gender presentation, and societal norms around said presentation- you can also make a guess to their name too in the same way actually,
infact there are some studies on this that show that certain names invoke certain kind of ideas on how someone who goes by it might look like; which is also obviously not always accurate, its just theres often not anywhere near as much societal bullshit for when your expectations dont match reality 
explicitly stating it means there is no ambiguity.