I'm not sure how I feel about that one. On the one hand, I know that when something like that happens the victim has a lot of feelings that can go against wanting that information to get out. They're embarrassed and ashamed, they don't want to be seen as damaged goods, they don't want to do something that could put them in the spotlight such as having to testify or give a statement to the police, etc etc. It's not unheard of for the police to be unsympathetic and "strongly encourage" them to not press charges. Having the world, or your little part of it, find out what happened to you is a re-traumatizing event. I've heard people say that if something happens to you then you owe it to any other future victims to come forward, but that's an easy thing to say when it hasn't happened to you. How did it suddenly become the victim's responsibility?
Abusers are very often close family friends or relatives, and it's not uncommon for family to side with them over the victim, at least as far as wanting it to be swept under the rug. You can be seen as a troublemaker, or worse, if you go forward with it. If it goes to court it's now a very public event, with the circle of people that knows what happened to you ballooning to who knows how many people. If the prosecutor fails to win a conviction, then what happens? If you are too young or unable to support yourself then you're now trapped and you've basically antagonized the abuser. If you're not then what do you do? Move far away from your entire support network? Beg a friend to let you live with them so you can feel safe enough to sleep some nights?
So if someone confides in you that something were done to them, are you going to take it upon yourself to do the right thing for them, when they're the ones that will face whatever the consequences are? Are you going to be there every time they start freaking out in the middle of the night because the situation has escalated and it's too much for them to handle?
On the other hand, abusers do need to be stopped somehow, before they hurt anyone else. So I don't know what the answer is.