These girls are just trying to come to terms with complex new feelings at that age, and giving guys what they think they want. It strikes me as unfair they then get taken advantage of for it and shamed for it by just about everyone. I wonder if people with your experiences feel a degree of identification with these girls, and are furious with them for making the same mistakes? I know that some feminists (for example) get very upset with other women they see as feeding into what abusive and manipulative men want (or are thought to want), or playing the same games with them. Anger may be understandable, but perhaps concern and guidance are more useful?

A metaphor - if someone wanders into traffic without looking, it may be understandable to be upset with them for getting needlessly hurt and also driving people's insurance rates up (especially if something similar once happened to you), but yelling at them while they are nursing a broken leg is not going to get them to change. Genuine empathy and concern followed by advice from the more experienced is better than reading them the riot act in the street.

I think I can understand your feelings about this. There are days I honestly would love to throw open my window and scream "Excuse me people ... when someone puts themselves in a position of vulnerability .. would you please STOP. TAKING. ADVANTAGE. OF. THEM. THANK YOU!!!" As for people who make themselves vulnerable, I think it's time for an honest and serious discussion with them.