[SheepWhisperer]

I tend to believe leftists to be closer to the BP and sociopath, but, as you stated they’re in the same family of disorders

[spankalib]

I believe you are correct. The differential diagnosis that 'professionals' use is this:

NPD feels like this
BPD feels like that

In my experience, NPDs are more (superficially) charming than BPDs.

As in all things NPD/BPD/sociopath, this too is only a mask.