The issue is not the age you come online, it's what happens when you do.
Delaying from 13 (COPPA) to 16 won't change a thing.
When I was a kid, I was obsessed with Home Alone -- I thought if I had one of those talkboys, I could get some changes made. But in an age where every teen has a recording device in their pocket, I continue to see the kinds of stories that made my blood boil... because when it came time to get the authorities involved they dragged their feet the entire time, if they would even file a report at all, and that inaction is paired with a "zero tolerance" policy on any kind of self defense that sends kids out into the world reluctant to give folks the rightful punch they deserve if they act out (and are entitled to give in most stand your ground states.)
Extending adolescence doesn't solve the root problems here, and conversely, more adults should reread a copy of "1984" and be a little more fearful they're held to the rules and norms they instill on the youth.
> Delaying from 13 (COPPA) to 16 won't change a thing.
There’s been a decent amount of studies to suggest it can actually, since you’ll be pushing the uptake of social media outside the peak age range where things like bullying, body image issues, grooming, etc. start to happen and, therefore, limiting the harm.
It’s also a time when a lot of life-habits start to get set down since 12-13 is when kids start having to assume more responsibility for themselves and begin learning how they manage their time, build their study habits, etc. Not being habituated into doomscrolling during that period seems like it can only be healthy. It’s not as if they’d be cut off from the internet entirely, they’d still have Wikipedia and all the boring, non-attention sapping parts of the web. And they’d still be able to direct-message or group-chat with their friends. They’re just spared the algorithmic feeds.