[lmm]

> Does your reasoning also apply for laws which ban underage smoking or underage alcohol consumption?

Up to a point, but AIUI there is credible medical evidence for those being disproportionately harmful (in physical, objectively verifiable ways) to the young. I think setting the same standard of harm and applying it to all ages is reasonable; maybe this law is based on some claim that social media harms children in a way it doesn't harm adults, but bluntly given how much the topic is biased and politicised I just don't trust today's social science establishment enough to justify this kind of law.