It's important to mention that a well maintained collection gets used more than one that is not reviewed. The "younger" the average age of your collection, the more it gets used. This isn't just because people don't like old books, but they don't like books that are yellowing, grey, worn, irrelevant, etc, etc. I recognize that libraries have many roles to play, but it is not the place of every library to play every role. A community public library should check out books, not store them. (There's obviously exceptions here. For example, my library maintains a local history collection).
Ultimately, for a public library there is much more going on than books. Wireless Internet, meeting rooms and simply its characteristic as a physical place (chairs, tables, etc.) are all part of why people support a library and having a new, clean and well maintained collection is part of increasing the library's appeal across all those areas.
I could certainly see the value of each community library having some space allocated to different "specialty" sections. That would make for a pretty rich loan inventory.
I've also been to many libraries that just feel like dumps and are not using space well. They have masses of cookbooks or old magazines that they call a special collection. There's a fetish surrounding "the book".
In the end this guy is arbitrarily deciding which books have value and which don't, which should ring an alarm bell for us. We might agree with what he saved, but we also don't know what he didn't feel was worth saving. That's why as systemic approach is so important.