Most of this debate makes more sense if the actual goal is liability reduction, not child safety. If it were genuinely about protecting kids, you'd regulate infinite scroll and algorithmic engagement optimization, not who can log in.
He is currently prepping to overthrow his local Pizzeria while the rest of us argue as if social media even exists anymore (it doesn't, it's just algorithmic TV now).
Better than muddying the waters trying to make it less addictive but then letting them on there when their brains aren't ready.
It doesn't have to be perfect and there will of course be easy workarounds to hid the warnings for people that want. The goal is to improve the situation though, not solve it perfectly. Like putting information about the dangers of smoking on packages of smokes; it doesn't stop people from smoking but it does make the danger very easy to learn.