At this point in his life (with wealth, fame, 23 novels and more than a dozen short story collections already achieved,), Updike says, "I can appreciate the advantages, for a writer, of youth and obscurity. You are not yet typecast. You can take a cold view of the entire literary scene."
Also, he adds, "You are full of material – your family, your friends, your region of the country, your generation – when it is fresh and seems urgently worth communicating to readers. No amount of learned skills can substitute for the feeling of having a lot to say, of bringing news."
He also notes that, "Elmore Leonard and P.D. James continue, into their 80s, to produce best-selling thrillers," but might one not argue that thrillers are a different genre, one more dependent on "learned skills" and less on "bringing news"?
And yet, you also have to wonder, what about the wisdom that ought to come with life experience? Shouldn't that make a literary work more readable rather than less?
One way or the other, Updike was clearly aiming his piece at older readers. But for the young who stumble upon it, perhaps it offers a bit of encouragement.
If you're you're young, obscure, and struggling to write – take heart. It may not feel that way to you, but at least according to Updike, the advantages are all on your side.