EDIT: Thinking about it more I _guess_ we are more misunderstanding each other then we are fundamentally disagreeing (through I guess we still are disagreeing :) )
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> I'd wager you're far far far from being aware of the 'reality most parents live in today',
I'm not (EDIT: As in I have enough parents in my live, through there may be larger cultural differences.)
and it's beyond my understanding how anyone can think treating a 13 and a 16 year one alike is a reasonable solution
similar all the things I have proposed gives parents the tooling needed
you make it sound like having an app fully controlled and replaceable by the parents is somehow removing power/choice from them. But nothing in it excludes parents from allowing or disallowing children to watch content from other age categories, potentially on a peace by peace basis
what it does is take the IRL system which isn't perfect but works reasonable good from how we e.g. handle the sale of movies and applies it to the digital world
including the option to ignore it
but we also have to recognize the reality that not all parents bother to even try to properly parent, and others are stressed, overworked and struggle. So having a triviale setup once and get some somewhat reasonable baseline solution is important (and yes it shouldn't be important, but IRL it is anyway)
similar I think it's important to realize that not just 18+ content can be harmful a barely not 18+ horror movie can still be quite traumatizing for some 13 year old. At the same time when children become 16+ you should have build a relation of trust with them where they shouldn't need to tell you or ask you for permission for everything not appropriate for 13 year olds on the internet. But while trust is grate you still would want to do more than that to keep them away from e.g. online gambling and some other sides. Which brings us back to having a baseline which works without spying on your child but still blocks some things off. I don't see how this is supposed to work without a having a 16+ age category between 13/12+ and 18+.
I guess we can probably agree on the fact that most content should only need the content age rating -> you decide (through parent controls) app direction. The OS --api--> Site/App direction is only really needed to serve a feed of "next" content and some other edge cases you could argue aren't in the best interest of children. But also there are better ways to fix those issues (through other means) IMHO. So I personally still would include it. At least for the age range 16+.