I would argue that a shared corpus that everyone has read is a key foundation to a society with rich and nuanced social intercourse. That doesn't mean everyone has read the same books, but there would be significant benefits in kids coming out of high school or college having all read 50 or 100 of the same great books (plus anything else they wanted to read).

I've had the pleasure of listening in on some discussions from high-school students that study classics meeting each other for the first time. Their discussions tend to be very different from what you'd hear from a typical high-school student. While other students might share the language, the ones who have read the same 50 or so great books tend to have a shared vocabulary of ideas at their disposal that doesn't seem to be there without the shared books.