This mentality is just foreign to me. If you're that scared stay locked down, no one is forcing you to go out. There's a weird authoritarianism to wanting to control other people from going back to regular life.
Additionally, there are several issues with leaving kids at home and in many cases it causes more problems than sending them back.
Lastly, they are not "forced" to send their kids back, they have alternatives. Admittedly, the alternatives may require a difficult life change (homeschool, private, moving etc.) but if they're already making the decision that it's better their kids stay home then they should be making some sacrifices to ensure they're receiving appropriate education. I can tell you they are not receiving a good education through online classes, or at least drastically worse than in person. Average kids k-12 age lack the ability to motivate themselves when left alone at home and there's data backing this up. It's also bad for their mental health.