Then the solution could be just like the solution to tobacco addiction: tax social media companies HARD, tax all advertising on social media 10x, 20x, or ban advertising on/for social media outright, ban advertising of kids products, ban showing use of social media in movies not rated 18, ... the problem will vanish just like cigarettes.

But no, that's not what governments are doing. They want control and surveillance.

Taxing or banning advertising alone would fix literally everything that is wrong with the web.

This is the most sensible solution to this problem I have read on HN in the 2 years I've been here. Think of the positive effects taxation would have: no whack-a-mole for every loophole the industry will find. No single fines after costly court battles that are basically pocket change for Zuckerberg et al. Adherence to polluter-pays-priciple. Make it so that if they stop advertising, the tax expires. Use the tax money for better infrastructue. Make the tax progressive - the more ads, the higher the tax.

Added benefit: even adults will be less exposed to addictive material.

What would be the cons of this?