The most common example of this is the tobacco industry and it's pretty much still there. Smaller, sure.
But do we really regulate the sugar industry killing millions every day? Or the car industries destroying the environment, cities and people? Oil industry perhaps?
There are many other examples of these. They are "regulated" in the strict sense, but in reality, they control governments and keep doing whatever they want.
I don't think anything will ever change in this scenario. After all, capitalism is the answer to every problem, right? /s
Hyperbole much? Only 150,000 people die each day worldwide from all causes.
If an industry was committing a literal holocaust every few weeks I think we would notice.
Again, the problem is not sharing. The problem is that they knowingly manipulate the sharing. How they do that is their problem.
I have no idea how to go about enforcing this. But it's impossible for me to look at it and say "just let it run it's natural course".
Regarding what should be regulated, I’d say that assisting genocide should be blocked for a start.
I'm really hoping we're headed towards decentralised federated social networks. With more control in the hands of the users. Like email + usenet on steroids. Not that those were perfect, but in that kind of environment, everybody can curate their own little corner, rather than putting all that in the hands of a single company.
We have international nuclear arms proliferation agreements that are reasonably effective. We keep the worst actors in the world from possessing biological weapons. But we cannot control what social media company Mark Zuckerberg let's loose on the world?
And we can't stop greed? Compared to the robber baron era we're all bleeding heart socialists. Change is possible and we can determine what technologies we want to live with as a society.
If twitter would only allow direct sharing between say, a personal circle of friends, I'd bet you a lot of money that we'd see very different outcomes.
At least they do that until genocide in Myanmar turns into a Facebook public relations problem.