I've noticed the first few comments on here are not ok with social media access being restricted based on age. I can't say it sits well with me either both as a parent and as someone who spent a bunch of those early years on IRC. I get that current social media isn't like IRC/Usenet but...we do need something that is.
I think it would be better to instruct what the kids can and cannot see in social media rather than this age based blanket ban. In the same way we have with movies and video games we could have age ratings and then give the parents control over what child account can see what content and define how the algorithms get to work for specific age groups.
I expect we are going to see swings one way and another in the following years.