It has been a thing for a while now and existed before the label was applied to it. Back at least to Greek times where in a major break from value norms preferring heterosexual intercourse for pleasure was once considered perverse. And despite how loud and much disproportionate effort put into it kinks are hardly the greatest evil or an actual issue in many cases. You say they should but what do they even gain from it except for power, control, and more blackmail potential?

It brings to mind a pet peeve of mine how morality seems to be used to mean how judgemental one is of those who are different or having a good time. I guess because looking down on others for being different is easier way to feel like a good person than say making sacrifices, standing up to injustice in the face of a society that agrees with it, helping others, advancing science or engineering, or well anything that is capable of actually making the world a better place.

See that's the thing, there are whole worlds of fetishes out there that people can't possibly be expected to understand. (This is one) So, the sort of fire-and-brimstone moralizing that you promote has been termed 'kink-shaming' (not by me, cmon man...)

Kink shaming and bigotry against sexual minorities is pretty common on Hacker News, yes. Case in point.

> Society has the right to make judgements about behaviors that are deplorable, undesirable, immoral, etc

Well, sure. Could you explain why you think BDSM is deplorable, undesirable, or immoral?