There is no way to really fix those problems by changing the school system. You can have bandaids, like providing free food at school, but that’s fixing the problem at the wrong level.
There is a difference between "parents always matter to a child's education" and "let's stop trying to improve schools cause what's the point". The latter is basically the same as "schools are pointless, why have them in the first place?". If you believe that, look at some countries that don't have schools...
I think every school should have the possibility to put your kid in an all-day school, I can't imagine the strain on single parents or parents where both have to work a lot otherwise.
Of course it's not possible to eliminate parents as an important factor of the success of your kid, but you can help.
As I understood it (not a parent and it not available when I was at school): You have all-day classes and "normal" classes at school. The kids in all-day classes stay together during the day and the kids in the other class go home, it is not an optional add-on. My niece is attending all-day school with a musical focus and likes it very much. All day classes differ between schools and classes, with school on 3-5 afternoons until 4 pm. Supervision is given for homework and studying for exams.
In addition to being a continually renewing supply of teachers, it provides an income stream for those who might really need it and financially incentivizes academic excellence.
why pay students to tutor? make tutoring younger kids part of the curriculum. teaching a skill is the best way to practice and internalize the skill for yourself.
montessori is already doing this very effectively.
We cannot rely on support from parents, the system we design needs to be thought of with parents out of the equation because in the case of the most vulnerable of kids they will not have parents that can help them. Special tutoring needs to be a part of the system, outsourcing the work will make things cheaper but it will complicate things for those struggling.
Kids in need should be our priority, because the ones that have supportive parents are really going to receive that support regardless.
I agree on everything else though. Content shouldn't be watered down, school needs to be a safe haven for kids in need. We should be having our most capable people thinking on how to improve the educational system so that we can truly bring everyone forward as we progress.