I'll also add that it isn't just a couple hours after school: It is holidays that parents don't get off work. It is summers without school. It is 6-8 hours after school while parents work second shift. It, in general, doesn't matter if your child is mature enough to stay home during the summer or late into the evening, the child care isn't for them.
She got told no because she didn't have recent work experience. Childcare simply doesn't count unless you are getting paid to watch other people's children.
I agree that everyone should have access to better child-rearing opportunities than are offered by school, especially public school in North America. I'd love to see homework eliminated, more time in school devoted to play, more tracking & opportunities for everyone to develop their strengths (be they calculus or auto mechanics), and the elimination of compulsory secondary schooling (let the kids come who want to come & make it rewarding enough that they do, rather than threatening to jail their parents to bring them to heel).
I am ignoring the aspects of your comment directed towards me personally.
This is exactly the type of situation ttul seems unaware of. The "only rich white people homeschool" trope is a myth from people who are unfamiliar with the much more complex reality of the situation.
* For starters, school doesn't last until 6:30pm unless you let it. Extracurriculars are extra. If you need afternoon child care (and most of us do), there may be less directed, more creative options available.
* Schools can make changes, and you can encourage your teacher / school / district to do so. Less homework (an idea which has some science behind it iiuc) at least. Maybe a later start time (although this runs into tension with parents' schedules).
Also, middle school that is from morning till 18:30 is definitely not the norm here. There is also this part where every single flaw of every educational system is assumed to be unchangeable and universal.
So it is not even like the argument would made sense.