Although he stated it in a rather offensive way, it can be so. Suppose PastorKevin, through no fault of his own, actually believes that foolishness about public schools. Then, loving his children, he keeps them out of public school.
Pretty much the way a person who knows that the same student will usually show higher attainment in a public school than a typical private one, will love his children enough to keep them out of private schools, or at least be very careful about which private school they attend.
Before anyone gets offended, read it carefully; most kids in private schools do better than the average public school student; but any particular student is more likely to do better in public school than the average private one. If you take two kids of same intelligence, with parents of the same intelligence, income, and educational background, the kid in public school will outdo the one in most private schools. The truly good private schools, the ones you have to register your kid prenatally to get in, are not the norm.
I "retired" years ago, to teach 8th grade science. In my part of the country, there are a lot of kids going to home school or various kinds of private schools. Many times, parents realize it's not working, by the time their kid is in early teens, and register them for public school. Most are bright, but with huge gaps in knowledge, especially in math and science. I spend a lot of time doing individual education plans for them. Most eventually catch up, but not all of them.
Granted, I do see the sample that didn't work out. But many came from quite costly private schools. The ones from Rev. Jone's Church Basement Academy are truly in trouble. Homeschoolers seem to be better; they don't know as much, but they usually have more respectable math and language tools. That can cover a lot of content deficiency.
Just my experience.