Internet communities are not a model of real life. They're not "technically" public, they are public. If somebody walked up behind you too close you'll know and you'll know whom. There is no such thing on the internet.
So let's not pretend they are similar and instead make people always aware that they are being blasted in public. That way they will not be mistaken, or take the moral hazard of security by obscurity, and instead seek out truly secure solutions.