It should be legally considered a crime against humanity for anyone under the age of 15 to access the internet outside of school

Think about it. Exactly what do children do on here except annoy real people and consume sludge content? Having access to the entirety of the internet and all of humanity's knowledge before you've even hit puberty or matured enough to have relatively informed opinions is rubbish.
It's also a matter of the wellbeing of the child, a kid that can freely browse the internet whenever they want are going to become reliant on it for everything. Giving children the opportunity to live their childhoods outside, playing with friends in parks, spending time with family and doing child things instead of staring at a screen all day is only beneficial. Kids must do kid things while they can, because looking back on your childhood and realising you spent most of it isolated and reclusive would be rather disturbing.