Saw a link on Twitter to this article on "Why we need physical books," which in my opinion begins badly, with some sloppy thinking:
The committed bibliophile is cousin to the obsessive, an easily seduced accumulator frequently struck with frisson. Cram your home with books, and you’re lovingly called a collector; cram it with old newspapers, and you’re derisively called a hoarder. But be honest: The collector is a hoarder, too—a discriminating and noble-minded hoarder, perhaps, but a hoarder just the same.
If you can't distinguish between a collector and a hoarder, then I submit that you're lost. A hoarder has a psychological problem: he doesn't merely collect—he collects indiscriminately, rarely bothering to organize his hoard. The hoard sits there in piles; pets can die, trapped inside those mounds of crap, and the hoarder won't even notice his pet's absence until the stink becomes impossible to deny. Hoarders are also completely unable to part with their trove, whereas avid bibliophiles will likely have learned, through reading, the virtue of nonattachment to material goods. If a bibliophile's library burns down, there will be sadness and anger for sure, but the loss of all those books won't fundamentally damage the book collector's psyche: he knows he can rebuild. Try removing even one item from a hoarder's hoard, though, and watch the overreaction. Bibliophiles care enough about their books to organize them and treat them with respect. They also come back to those books, avidly rereading, relearning, reliving. What does a hoarder do with his trash except guard it and warn other people not to mess with it? If you can't tell a hoarder from a bibliophile, then you can't tell a pig from a librarian.
The author of this article seems to be saying that a collector is a type of hoarder. If anything, if one truly is a species of the other (and I'm not convinced this is necessarily the case), I'd say he has it backward: a hoarder is an insane form of collector.