His face in repose always looks as if he very angry or miserable or unhappy or perturbed or fershimmered or unsettled or gobstomped.
His face is ALWAYS animated at one of his hate rallies and is all over the place with grimace smile smirk snark sneer. Like a kaleidoscope of ugly. For effect? Mebbe. His peeps seem to adore every expression he can muster up.
But in repose? A very unhappy homo sap. Why do you think that is? Stern is usually what he looks like. Maybe he is trying to appear to be very manly and firm and in charge. But seriously I am not convinced.