[freshm087]

I'm not a native speaker, and may miss some nuances, but promiscuous is defined as "having multiple sexual partners" by my dictionary which I think is as neutral as possible.

Promiscuity is at first, and foremost was (and still is, in spite of contraception availability) practically more acceptable for men. And monogomy among other things is a constraint on men's behavior - forcing to accept social, and economic responsibilities before fulfilling sexual urges. You are right noting that it rarely worked in any absolute way, but I don't think any law, whether written, or not can be 100% effectively implemented. People steal all the time, but I suppose you wouldn't say it's because related norms are not enforced, right? Monogomy's real application varied over times, cultures, and spaces, but it was certainly enforced by societal pressure, and legally too. Actually, in my father's youth years (and it's not that deep in history) it was hard to have sex before marriage. It was for sure possible, but dangerous for reputation of both participants (probably more damaging for a women, but damaging for both nevertheless). It wasn't US, and "sexual revolution" came to us much later, so that's probably why you may have no living witnesses for it.

Also, prostitution was until quite recent times seen as a moral compromise acceptable only because of long serving soldiers, and sailors. In most societies it wasn't ok for a family man to visit a house of prostitution, and in some cases it was even criminalized.

[Steuard]

I am a native speaker, and "promiscuous" is definitely a negative, pejorative term. (Dictionary definitions are good at capturing the denotation of a word, but are sometimes less good at explaining its connotations. If your dictionary lists additional/alternate definitions of this one that apply in non-sexual contexts, look at those to see if they appear to carry positive or negative implications.)

[jessaustin]

It's clear what is being discussed here, because "promiscuity" has a simple understandable meaning. In certain contexts the word has a negative connotation, but only because those contexts morally disapprove of the condition the word describes. One would have hoped that "native speakers" could have offered a different, more suitable word to employ in this discussion, rather than just ruling the discussion out of bounds because they don't like this particular word.

[fxbl0i]

Promiscuous is a pejorative term because the act itself is socially seen as negative. There is no way of describing promiscuous behaviour positively, so the choice of word is irrelevant.