To be fair “non-harassing way” is a bit subjective. I’ve seen dudes have success with methods that I would consider “harassing”. I’ve also seen guys condemned as creeps for approaching women at what I’d consider a reasonable time & place.

Yep; and this is a big problem of mine. As I’m quite pessimistic my default assumption is that a simple greeting is likely to result in a negative reaction. A similar problem is approaching individuals / groups (for whatever reason) in general: are they free to talk to or is that a closed group who would feel bothered? Hard to see from the outside.

You have to develop your sense of empathy and feel it out on a case by case basis. Pretending this black and white doesn’t help anybody.

I agree. And as long as a no is respected promptly, no harm should be done by trying. But tell this my anxiety…