No, there is no law banning anything these companies did. You know this; that's why you didn't link to the law in your comment.

There should be a law banning the addictive practices of these apps. Until there is, fining the companies that make these apps is unjust.

Not how the legal system works.

There are laws enabling the judiciary to operate as it has to give plaintiffs a platform in the first place, in the absence of specific laws because legislative bodies are slow to adopt new laws for various excuses.

For example; not hard to pay off a handful of legislators to vote no. Then what? People just suck up living at the mercy of the rich?

Judiciary has leeway to allow such cases and outcomes to bubble up useful context for changes to law. Longstanding precedent and in some cases is codified in law itself.

The lack of a specific legal language banning social media actions is also irrelevant because of similarities to other situations that are enshrined in law. That human biology is susceptible to psychological manipulation is already well understood. Tiny little difference in legal context does not invalidate known truth of biology.

Society doesn't exist in your head alone and has existed for some time. Much of this is not truly new territory.

Stop embarrassing yourself.