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Obligatory Sold a Story podcast link.
I can't help but feel that a lot of this is deliberate, the end result of decades of dismantling the public education system to further divide kids into the upper class in private schools, religious fundamentalists in home schooling, and everyone else abandoned to keep the population uneducated and in worse economic precarity.
Somebody please tell me that the kids are alright 
This is primarily the result of neoliberalism, yeah. Budgets getting crushed everywhere for decades, not keeping up with inflation, all while being asked to take on more and more work - largely work induced by problems of poverty, itself an intentional creation of neoliberalism. Lower wages also mean it's harder for a parent to spend time with their kids teaching them, helping with homework, having a preschool, helping socialize them. This includes not only an inability to have a stay-at-home parent, but also less time even for working parents, who must pick up longer hours, farther away, and at less regular hours.
As a revealing counterexample, after-school programs have been shown to be widely beneficial for a huge number of outcomes, including academic performance. Simply having something enriching to do, supervised, after school. I think they are mostly smoothing over issues of poverty.
The destruction of the teaching profession is part of this as well. I'd try to be a teacher myself if it didn't mean poverty and 70 hour weeks and an inability to properly teach students due to structural issues like poor teacher:student ratios.
The education system also refuses to pay teachers for those after school programs, relying on teachers volunteering their time to run them