I'm sorry for your experience and I won't dive into your response to it, but as to your points they're all incredibly hand-wavey and #2 & #3 are especially magical thinking. This isn't to say that they aren't so, but unless it's possible to prove them they're pretty tenuous reasons with which to shape policy.
Think of it what you will. But to #2, googling randomly, http://www.nsvrc.org/sites/default/files/publications_nsvrc_... claims that only 12% of child sexual abuse is reported to the
authorities, and cites a study on the topic. The majority of such studies that I've seen are based on surveys.
On #3, anyone with experience in how the legal system works will agree that while how often it happens may be hard to quantify, but it certainly does happen. And probably not very rarely.
