No National Socialist wants to call themselves National Socialists. It's a trend I've noticed. They, and the Left, are both more prepared to call the National Socialist a Nazi, because it helps to disguise the problem at play. Internationalist Socialists don't want Socialism to be tied to National Socialism, because it exposes Socialism for what it is. National Socialists don't say that they're National Socialists because they don't want anyone to recognize that they are explicit Leftists, particularly on the dissident right which they seek to destroy.

There is also a moral judgement component to it. I do care about the National Socialist's feelings: and he should feel bad. This is because, as a Socialist, he's a bad person with serious personal faults who is politicizing them into a schizophrenic historical dialectic centered around an international jewish conspiracy against him. He is also so fundamentally power-hungry that his actions are directly contradictory to the claim that he has any intent on helping either his nation, or any other category he claims to advocate for.

I would also call a Communist a "Pinko" for much the same reason.