As a studier of Freud, I can't help myself. Beyond the Pleasure Principle discusses various masochistic paraphilias. Freud theorized that an interest in cuckoldry arises in the Oedipal stage, in children that fail to grow emotionally attached to their mother. Thus they acquiesce to an observational role with the woman they care about, accepting - and even taking comfort in - the fact that a stronger man (i.e. the paternal figure) deserves her love more than they do.
I get where you're coming from, Cutieson, I don't like cuckoldry either. I don't think it's healthy. However, Rouge has a point, kinkshaming is a bummer
E: To answer op, I think it's both: a descriptive insult, no different from "pervert" for example. If somebody likes to sniff butts, calling them a pervert is a valid description, just not a very polite one. I would use the term "cultured".