That's fair. I was using a quick and simple soundbyte to push the idea that insulting people with mental illnesses is bad. When I take a nuanced and patient approach, people usually accuse me of defending abusers and go off on a wild tangent. I've found it's important to cement people's ideas of who I am and where my criticism is coming from within the first 10 seconds of the interaction. If it takes any longer than that, they assume since I dared to disagree with them that I must be the enemy, and they project everything they disagree with onto me.

Since you're clearly appreciative of nuance, I'll use the nuanced argument with you. While Elon Musk may have NPD, it would be medical malpractice for a registered psychiatrist to make that judgement without having had a session with him. There are regulations against that sort of behaviour for good reason. It's called the Goldwater Rule. https://en.m.wikipedia.org/wiki/Goldwater_rule

The danger of diagnosing public figures without the proper rigour is that people's idea of what a pwNPD is are informed by stereotypes, and those stereotypes inform future armchair diagnoses. It becomes an ouroboros with no actual grounding in science. That's why everyone thinks psychopaths are killers, narcissists are abusers, and obsessive-compulsives are neat freaks. These stereotypes can encourage abuse by the public of people with mental disorders.