The blog post is about rare books. Meaning, AI companies scanning and destroying rare books.

Yes, read more carefully: one copy. Do you panic when the "wrong person" buys a single rare book?

The issue is that the copyright holders and book publishers make it hard to make more copies, not that somebody bought a single copy of a book, no matter how rare.

If you could print any book on demand (paying for it), the issue would vanish instantly. And who makes that decision?