I think this is a case where the OP's link left out information -
I'd wager the kids' parents have said before this happened that they'd take the kids to another country like the US. Taking their passports prevents this kind of fleeing.
OP's link is a link to a US homeschooling advocacy organization. So you're right, the problem is the link itself - not a particularly constructive thing to post on HN.
I'd wager the kids' parents have said before this happened that they'd take the kids to another country like the US. Taking their passports prevents this kind of fleeing.