Look at it from their point of view. If you identify as something other than what you were born as, what is to stop you from changing that from time to time? Yo

Look at it from their point of view. If you identify as something other than what you were born as, what is to stop you from changing that from time to time? You may, at a later junction, feel more comfortable with your birth gender. Thus the option "decline to self-identify" gives you everything you need to say.