I don't strongly disagree on any particular point, per se, but the fact that the author's thoughts are rooted in a religious worldview felt like it was snuck in there at the end:
"Moreover, this world is fallen, so it is by nature flawed...The utopian visions that animate real places...seek to remake humanity and society in someone’s image—and that is not the image of the Creator."
For further context, the website it's on is "The Russel Kirk Center for Cultural Renewal"; from its Wikipedia page: "The Center is known for promoting traditionalist conservatism and regularly publishing Studies in Burke and His Time and The University Bookman, the oldest conservative book review in the United States."
Not that these things invalidate it necessarily, but they're important context to place it in.
Overall I'd say the article is more an argument about semantic nuance than a grand social commentary. Probably a valid semantic critique, but nonetheless.
It seems to me that public health concerns are a pretty reasonable line to draw. Flat earthers are weird, but they affect no one outside of themselves (how can anyone act on living on a flat earth?).
More generally, effects that have the ability to meaningfully and physically compound among both children and adults seem pretty obvious targets. Ideas that can compound in adults are ok, because they're rational actors under the law, but for example teaching kids to teach other kids pro-anorexia propaganda is not, because it compounds to a public health problem that they never could have consented to deal with.
