It was my job for a decade to try to keep tweens and teens safe online. Let me tell you what you already know: no law or technology can do it. There are no lengths kids won't go to to talk to friends without prying eyes. The harder you try to lock it down, the dodgier their solutions will be.
@mttaggart are there any studies or anything you can link to? I want to participate in this discussion but I'm not sure where to start and I want to back up my arguments

@Surlytom I'm unaware of any direct studies of this type, in part because I can't imagine an IRB signing off on an experimental design that guarantees exposing minors to inappropriate/harmful content.

But here's an anecdote: when we had the most restrictive filters and monitors in place, you know where our 5th graders started creating abusive chats?

Google Docs. The tool they were expected to use for classwork. And even when Google (eventually) created some measure of monitoring for that platform, the kids immediately learned how to use emoji to speak in code to avoid said filters.

They always find a way.