I was raised in a very "pro-natural hair" family. You know the stories some women tell about their families' horrible reactions to their BCs? That's how MY parents would react if I ever came home with a perm.
Coming from that environment, I NEVER heard "nappy" used in a pejorative sense. Or in a positive sense, for that matter. Nappy just WAS, the way curly (or straight) IS. Neither bad nor good, inherently. When my mom had just finished doing my hair and it was fresh, it was "beautiful nappy hair", when I desperately needed a refresh, it was "get that nappy head over here" lol. In my experience, black natural hair often isn't the same as "curly" hair. Considering that, doesn't it make sense to have a unique name?
It's kind of narrow-minded to assume that, because you have negative associations with the word, everyone does.
And no, I don't put the word on par with the "n" word and that reclamation nonsense. I've yet to see evidence that "nappy" was originally used by oppressors the way the "n" word was. Growing up, it was always ignorant black folks calling my hair bad because it was nappy. We'd be "reclaiming" it from self-hating black people...not quite the same.
That said, there are a few older threads on this topic. You should try a search if you're interested