That said: banning encryption is not the answer to this.
It's almost always the victim's parent/caretaker or other close relation-- but they always "seem totally normal" so nobody wants to believe it's happening and will excuse or look past all sorts of shitty behavior that, if it were performed by some random, would elicit disgust and antipathy and cause them to be run out of town.
I'm currently dealing with an abuse case. The family is uncooperative because they don't believe the evidence presented, and the victim has been coached into protecting the perpetrator. So the abuse will continue.
Is it? From a quick search, I cannot find any academic papers that support this claim. However, I see some news articles that claim this.
https://www.tandfonline.com/doi/abs/10.1080/0735648X.2011.63...
https://journals.sagepub.com/doi/abs/10.1177/104398621140589...
This paper mentions "turnover intentions", which seems broadly defined in the methodologies.