I have to say that many of today's junior novels are much better than those available in the 50s. Of course, some aren't, but, there are some real classics of children's literature.
I also have to say that I find some contemporary authors unreadable -- even some of the lauded ones -- because their prose is too (what I call) "brittle."
I was made to read Wuthering Heights when I was in school and I thought it was absolutely brilliant. I went out and bought myself a hard back copy to keep.
Many people think there is a time of life to read a book. In other words, we are sometimes too young for a book -- which may be the case with many of the books we are made to read in school -- and, other books read when we are young, may prove to be vapid or simply clever when read after a few years real life experience and intellectual growth.
I am currently rereading Pride and Prejudice. I had trouble reading it when I was a high school kid because Lizzy's parents called each other Mr and Mrs. Bennett. (There are many books that turned me off completely at the first sentence: "Howard Roark laughed." "He was an inch, perhaps two, less than six feet tall." "Scarlett O'Hara was not beautiful." On the other hand, there is a book that I loved as a child that endeared itself to me as a 50 plus person because the first sentence or a sentence on the first page is, "I hate being poor.") When I got past their names, I enjoyed the book, which I am reading now after seeing the wonderful recent movie. I find myself liberated by the fact that I don't have to read for plot and can enjoy what Austen has to say, enhanced by the fact that I read the director of the film called her the first English realist.