I'm bothered that this article seems to believe that the rise in homeschooling (in large part by unqualified parents using low-quality textbooks and ill-considered strategies) is another example of people 'opting out' of some particular brand of oppression by the State, and that doing so will increase supply, or something? As far as I'm concerned, students have a right to a high quality education because without one…
No, that's exactly what being a minor means. One's parents have the right to teach one whatever values, facts and fictions they wish, while one is a minor.
But don't worry too hard about it: teaching is _not_ hard. Almost any parent who cares enough to homeschool is capable of teaching his or her children better than a public school would (which is not a very high bar to clear).
As for your anecdotal belief that the homeschooling families you encountered were incapable, I wonder if it was really your belief that they would not teach what _you_ think is true and correct.