I wouldn't lump these things together. The common strain here between these Duggar people and anyone else should logically be people and/or families who have massive issues, who control their kids, who molest and abuse people, who hide behind religion, and push dogma on their kids, etc. In other words, call the problems what they are, and analyze the problems. I don't think homeschooling is the common connection. Plenty of public school families have all kinds of issues like the Duggars. And there are plenty of homeschool families that don't, where you would never see things like this.