> So it makes sense to make it illegal for those companies to provide services to children

I'm in favour of this, so long as the restriction is narrow. Children shouldn't be on Facebook, but they should be able to participate in the RuneScape forums under a pseudonym, or contribute to Wikipedia (provided they understand the "no, nothing can be deleted ever" nature of the edit history).

However, most of the things we'd want to prohibit for children, aren't actually good for anyone. It would be much easier, in one sense, to blanket-ban the bad guys: no new accounts may be created on services like Facebook or Discord, unless they change their ways.