I disagree- I think it's not much different than working at a distillery or cigar company (wrappery?). Social media is a vice not very different than whiskey or cigars- they're addictive, feel good in the short term, and are problematic to have too much or to do habitually. But we still let people indulge in them because they're fine in small quantities for responsible adults, and we expect that parents will not let their kids have access to them.

The only differences as far as I can see are in buying- a child could technically buy a phone for themself if they had the money and create an account on Instagram for free, and in cultural recognition of social media as a vice, which I believe is starting to change.

The overall point is, the law should assume that adults are reasonably intelligent and responsible people, and that parents should be the ones responsible for parenting their own children their own way.