https://en.wikipedia.org/wiki/Narcissistic_personality_disorder#CITEREFCaligorLevyYeomans2015

It is often co-morbid with other mental disorders and associated with significant functional impairment and psychosocial disability.[1]

It's a disability. People with NPD (that's person first language) struggle with identity, self-esteem regulation, skill development, and interpersonal problems. Both due to society's treatment of us, and the structure of our self-identity in the brain. I recommend reading the DSM-5's appendix on personality disorders. The new model of NPD is as a system of struggles with identity formation and interpersonal interaction.

https://www.psi.uba.ar/academica/carrerasdegrado/psicologia/sitios_catedras/practicas_profesionales/820_clinica_tr_personalidad_psicosis/material/dsm.pdf

For an egotypical, the process by which you made your identity as a child felt effortless, because of the support of your parents. And it's easy for you to imagine that it's that easy for everyone.

But I don't feel like a real person. My understanding of Myself is artificial. I made Myself up. And it's a fragile ego, so I frequently have to rebuild parts of it. I can change it without much effort. My way of interacting with the world is different than yours, because we both use our selves to do that, and how our selves function is different.

So basically NPD is neurodivergence because the brain works different. And we know the brain works different, because the mind works different.

I agree there are differences between these two different ND conditions. You've pointed out some genuine differences. I'm certainly not saying they're identical. But there are also many similarities, like those I wrote about yesterday.

And the disability from My NPD isn't just a matter of how I treat others. My sense of self is... fundamentally artificial. I made Myself up, and I'm very aware of that fact, because I can change it without much effort, and other people can damage it without even meaning to. I don't feel like a real person. And I'm fine with that, but we live in a society where beings are expected to be real and to be people. My lack of artifice about My artificiality creeps people out.

I wish we lived in a society where everyone had NPD, because then social norms would be so much less effortful to Me, and I'd catch fewer ego injuries because people would know how to be sensitive about that stuff. Communicating with other NPD folks is easy in a way I don't experience with egotypicals. Communicating with autistic NPD folk is often effortless.