Because the tools don't work, and are too fragmentary and burdensome.
Would you prefer to inform each movie theater in town which movies your child is permitted to watch? Or just rely on the rating system that applies to most movies and is honored by most theatres?
Parents want one setting that says "this is a child" and then expect online platforms to respond appropriately. As we expect and mostly have in the real world.
If parents want that solution, then the proper thing is for someone to build that solution and make a fortune selling it, IMO.
> Parents want one setting that says "this is a child" and then expect online platforms to respond appropriately.
This law does not do that. It breaks the age of children into several buckets so that platforms, websites, and advertisers can target specific demographics. They won't "respond appropriately" they'll just use this data point as another way to improve how they exploit children online. Now every pedo with a website can tell how old the kid is so they can better adjust their grooming for that age bracket.