https://www.gimletmedia.com/reply-all/119-no-more-safe-harbo...
There is significant evidence and research showing that these services helped protect prostitutes and kept many of them safe. They used technology and private forums to inform one another about dangerous Johns and screen potential customers.
Where teens being trafficked? Probably. But that's an entirely different problem, one of getting more social services available to help teenagers if their domestic situations turn bad; so they have some place to go and don't end up on the streets or being taken by pimps.
Since these services went away, sex workers are already reporting people they know disappearing, or being assaulted.