Underage drinking is still more common than it should be, despite strict laws. The point is, it doesn't do any good to go after the consumer, regardless of age. in order to make a meaningful impact, legislation would have to destroy or significantly neuter social media companies altogether, globally. Anything else will be a disappointment.

The more effective way to reduce these harms is through social/cultural change, but that's easier said than done.

lol are you serious