I sometimes wonder why I collect books. The Internet provides enough info on most subjects I'm casually interested in; but books still provide the satiation of my deeper curiosities. For example, I recently began photographing the carpenter Gothic churches built in late 19th century here in Florida. That interest led me to books on Gothic Revival, then back to the Gothic beginnings in France. The result is about 10 books just on history of Gothic churches.
For photography, however, I seem to buy only 1-2 monographs for each photographer I'm interested in. That still has led to over 300 monographs some of which are on your list above. I could of course just peruse the Internet for those photographers, but physically holding a collection of their prints is almost as satisfying as a gallery exhibit. Many predict the demise of paper prints and books, but digital display does not do justice to a real print (or well-printed facsimile as in books).