

That is true. The effects of social media shall not be applied to just the children and consequently also the teens, but to all the people. Such laws are basically half measures which do more harm than good.
Regulation is what should be done; if efficiency is what we strive for, why aren’t the corporations responsible for this not being regulated. A safe internet shall be safe for all - It is important to realise children grow up to be teenagers then adults just like everyone, such a disproportionate effort is completely unacceptable.
Why is it that we look at the ways the children circumvent this ban but not corporations? This law is not made for the people, it is made for the corporations.
Unfortunately not. There are many individuals which are dissapointed due to the failed efforts of the blanket bans, but ultimately stand for them.
Aside from that, this problem is defacto already partially solved. As you said parental supervision - parental controls are proven to be extremely effective at what they do, if they are utilised correctly.
But even so, you are highlighting the need for separation of developing minds even if that statement has no basis on age. If you’re serious about it, then the whole internet should be designed to be safe for everyone.