Addendum: Of course, you could easily say that the purpose of a pronoun is also to denote gender, and that refusing to do so by being more vague is an insult; but I don’t think it’s a good direction to take the language to make gender more embedded in our language. Specifying gender should be optional for when it is necessary, not an obligation to be made whenever you refer to someone. They are more than just their gender identity, and needing to refer to it whenever you refer to them (other than by name) is counterproductive to maintaining that separation, and is also semantically simpler.
Addendum: Of course, you could easily say that the purpose of a pronoun is also to denote gender, and that refusing to do so by being more vague is an insult; but I don’t think it’s a good direction to take the language to make gender more embedded in our language. Specifying gender should be optional for when it is necessary, not an obligation to be made whenever you refer to someone. They are more than just their gender identity, and needing to refer to it whenever you refer to them (other than by name) is counterproductive to maintaining that separation, and is also semantically simpler.