My own website has a bulletin board that offers a personalized list of messages after you login: whatever threads you have not yet read. And so do many other websites of this style. So this cannot be a differentiating aspect.
So it is advertisements where we should draw the line -- websites with advertisements should require age checks?
It clearly isn't just a singular data point that is a True or False that would include a site in the ban.
Perhaps it should be, "If I had a 12 year old daughter, do I want her to have easy access to pornography, self harm material and the ability to receive private messages from a 45 year old registered sex offender?"
I get your point - "Where is the line in the sand?" and it's a valid point but no need to argue in bad faith.
I do think the "wont somebody think of the children" arguments are in bad faith though, and I say this as a father.
If parents are concerned about this, why let them on the Internet? Why not use parental control systems? Why not teach your children healthy sex education, how to deal with their feelings, and to tell old creeps to fuck off?
Now explain that nuance to an 80 yr old law maker who hates the damn email.
It's actually the same as the average age of voting-age French citizens, so they are quite representative on this regard.
They hate social media because it gives people the power to talk in public about them with near impunity. They want to go back to the old days when if you wrote a letter to the newspaper about potential corruption or wrongdoing among the "more equal animals" you'd get pulled over for a light out whenever you went through that town for the next 20yr.
If you think you have even near impunity on social media, I have a bridge to sell you. Even a town to go with it.
I specifically said "near" impunity. If you do something bad enough they'll come after you but even then if your gripes are legitimate that's likely to amplify it.
Surely you're not honestly claiming that there is not a significant practical difference between modern internet criticism and the old ways when messaging that could reach the broad public was far thoroughly gated by people and things that had more stake in the power structure.
But even now, a lot of messages are lost on the internet. And the internet is only decentralized for messages propagation, not for access.