I know what you mean, but I think the issue is not social media, but rather big corporations being shitty. PepsiCo makes addictive beverages that cause people develop to diabetes and heart disease, but that doesn't mean beverages should be illegal. I think it would be better to regulate or ban the specifically harmful things, rather than a blanket ban on something that is actually useful. And like you alluded to, banning social media could easily lead to a general crackdown on freedom of expression, journalism, etc, now that it is the primary way people communicate with one another.

I'll also add that I'm not specifically opposed to banning minors from using social media. It would probably also be better if it was illegal for children to buy their own soda tbh.