This article is interesting . To me classic the writer should be dead or semiretired and haven't written much if anything for a generation.
This author seems to dislike James Joyce, two of his are on the list.
Ayn Rand is more political diatribes then novels so yes lets not count hers.
To Kill A Mockingbird is one of the rarest of gems a novel that when written should have been considered a future classic and definately is one today. This should not be on the list.
Future classics should be Jodi Picoult's Saving Faith and The Pact.
If in 30 years Janet Evanovich's Stephanie Plum books are called classics, my scream will be heard around the world. Same with James Patterson.