They could give them anything more than minuscule slaps on the wrist for their long list of transgressions:

1. Anti competitive behavior

2. Advertising fraud (incredible how frequently their view/click counters are found to have bugs which consistently benefit FB)

3. Privacy violations (shadow profiles esp for minors)

There are dozens of bases upon which Facebook can be punished for being a horrendous contribution to society.

You could use the same tactics that were used to discourage smoking: forbid it for minors, force them to display a "health" warning banner, start a public health campaign shaming people for using it, etc.

Shower thought: we've been (some countries more some less, some earlier some later) in a collective physical lockdown which was challenging to deal with but most people coped with it just fine. Surely, technology helped we had our entertainment and we managed to maintain some social bonds with friends and family via video.

What if we engineer an "information lockdown"? Three months of no internet, no TV, only word of mouth communication of official billboards at the local level.

Would we cope with that just fine? Would it help us learn somethings about us and learn to appreciate things, as the physical lock down has done for some things (like cooking, time with family, etc)