At the point of sharing photos and Photoshopping someone to ridicule them, this isn't an offhand comment said in frustration. This is planned and executed ridicule and mockery. He's exposing them because he thought their "friends" should know who they are and what they are doing. Not for the intent of "hurting everyone else involved intentionally due to a sense of self righteousness". Whether you agree with what he thought or not, it's not narcissism (by itself).

It's also super bizarre that you want privacy for them when they are fucking sharing photos (the context reading they were private) and sharing "raunchy texts". Where was the privacy for their victims huh? They deserve what they got.

I don't know about you, but I am very reluctant to insult others, even in private conversations, even if they might deserve it

I always try to approach things constructively, because in the end, those patterns and thoughts bleed out into the world and your behaviour

And do keep in mind, even from the poster's side of the story, it sounds pretty darn bad, and people have a tendency to downplay their side's wrongdoings and elevate the other side's. Chances are, it was probably quite bad

If there's people in my life that go around talking badly about other like that, even in private.. yeah, I'd want to stay the hell away from them too. It's just a massive warming sign, and you're going to be the target sooner or later. And you don't want a coordinated group acting in bad faith against you