The "eternal greats" aren't actually always that eternal
Alan Jacobs notes that while we may think our current taste in dead authors consists of the folks who have been vindicated by history, literary tastes do change, even about decades past:
. . . canons change over time. John Donne was forgotten for 250 years, until T. S. Eliot celebrated him and altered everyone’s understanding of what early 17th-century literature was all about. The town I live in is full of elementary schools named after American writers, some of whom are still famous (Emerson, Hawthorne), some of whom are still rather well known (Longfellow), and some of whom have been nearly forgotten (Whittier, Lowell).
It may seem obvious to us now that Nathaniel Hawthorne will always be considered a far greater writer than James Greenleaf Whittier, but let’s not be too sure. Different cultural and historical circumstances bring out certain writerly virtues and make others seem less important. Perhaps a hundred years from now people will look at The Colophon’s list and think, “Well, of course James Truslow Adams is a magnificent genius, but who the hell is Robert Frost?”