I mean, the court case is about these platforms being addictive to kids, so if they said "accounts for users under X years have the algo and time caps delegated to their parents' account by default" it'd go along way to negate what they're being accused of.

They've already built all the tools they need around this at the moment, it's just they give them to advertisers rather than end-users.

"Let the parents manage it" is, unfortunately, part of the reason we're in this situation in the first place.