Nice approach. I personally can't force myself to get rid of books that I've read, which is not very rational, because I very rarely reread books. But other stuff I try to get rid of, or not buy at all.
I now have children who want to read them.
Having one less book shelf is effectively saving enough per year that you could probably pay for buying back all the books you'd ever re-read on that shelf. And if you ever move, the cost and annoyance of keeping books just skyrockets.
I have a lot of books I love, but 90% of books are essentially disposable vehicles for information of transient value.
Also, for text-only, transient stuff like business books and history books (that I'm unlikely to read twice), I buy a lot of Kindle stuff now.
Still can get past the cognitive dissonance of letting my bookshelf go.
The decision making is forcing valuable reflections!