I’ve gotta say I don’t think it’s wise to diagnose people like this. Diagnostic categories are imperfect, heavily influenced by social norms and prejudices, and used to categorize and control people just as often as they are used to help people get needed treatment. Trump is a bad person. We know that without a doubt. I think trying to label it as an illness, or debating if a certain condition is or is not responsible for his behavior, misses the point (and kinda ignores how the dsm’s very messy model of mental illness categories functions in practice.) Some people suck, no clinical explanation needed. Diagnosis is for when you are alone with a therapist trying to figure out what you need. It shouldn’t be a shorthand for making inferences about strangers, or papering over abusive behavior. Diagnoses are socially determined and have a history of being weaponized against people who, say, have not serially sexually assaulted anyone or tried to do a coup. The guy is a bad duded who also loves attention, that’s all. I think it’s better for everyone if we don’t try to medicalize it, because people who have been through the medical diagnosis machine are (often seriously) harmed when evil monsters become what most people automatically think of when they hear about p ‘mental illness’. Trump is just a horrible person. That’s all. He knows what he’s doing and he’s responsible for it.

You're right that neurodivergence in general doesn't require disability, but NPD specifically does. If you wanted to claim he has autism, your argument he's a perfectly functional person would hold water, though it would be an equally silly thing to argue. But you're arguing he has NPD, which is associated with significant psychosocial impairment typically impacting career, friendships, romance, family, and general social status. Trump is demonstrably very socially gifted and does not struggle with being accepted by society or the people around him. You're talking as though he overcame tremendous adversity to become president, but that's not true. The deck was stacked in his favour from the start!