And that, in turn, disadvantages students with working parents, or with parents that don't have the skill or experience to guide them to higher achievement.
It may sound awful to trust "the state" to handle education independently, but the alternatives are usually worse.
One of the most important epiphanies in my life was realizing that some parents don't care at all about their kids, some are jealous of them and actively sabotage them and that some systematically abuse them for entertainment.
It is also why I'm get angry when people push others to have children; many people should not raise children.
Meaning: They would care more for their children if they had the energy and power to do so. And some of those will also rationalize their inability to spend the energy as not wanting to do it.
Parents spending time with kids over activities that are mutually pleasant or just talking or doing needed activities are valuable. Third party organized nonsense that just needs to be done has no intrinsic "time together" value.
And in case of bad parents, it puts the kid at mercy of bad parent even more.
What if public school is awful, and the only reason it looks decent is that some parents are picking up the slack? What would happen if you cut those parents out of the system?