Your argument hinges on the assumption that porn and gore etc. have worse impact on kids. I don’t think there’s a concensus on that. One might argue that porn and gore could have been found in print before the internet, but that social media have a more novel impact.

I personally like the theory that most kids problems are actually attributable to family issues. That kids in solid family environment/upbringing will not be “destroyed” by computer games, porn, gore (2 girls 1 cup anyone?), or social media. But that’s also just a theory.

I do not think it is about seeing certain things, that exist in the adult world. That is surely a side effect that one wants, though, protecting minors from a world that they can not comprehend.

I think it is about algorithms targeting you all the time for hours in favour of a company. We see the effects every day. No attention span. Instant gratification. The next kick.

If things in the internet didn’t impact kids or people then people wouldn’t get up in arms about non-PC content, but we know many different kinds of people only want thrown own kind of content out there and would prefer to limit or ban ideas they disagree with.