I think the evidence that school is extremely important is weak at best. For example, students who don't learn any math until 5th grade caught up to their peers by 6th grade: https://www.psychologytoday.com/intl/blog/freedom-learn/2010...
There have been other studies where students who had to miss large amounts of school due to a natural disaster caught up within a few years and there was no measurable difference in adulthood.