I don't assume that. I do assume that the majority of those who write primarily to entertain, in the way a TV sitcom entertains (and there have been writers doing just that for at least a couple of centuries), show a higher probability of dropping out of sight.
Currently we continue to have translations of works by Homer, Aristophanes, Chaucer (Old English isn't an easy read for most of us, so, yes, translations), Cervantes, Mallory, Flaubert, Balzac, Dostoyevski, Tolstoy, and dozens of others on the bookshelves; we also continue to see editions of Austen, the Brontes, Dickens, Hemingway, Faulkner, and so on, still on the stands. They are not there solely because of curiculums. A few years ago publishers noticed just how well the classics were selling. Not enough to get on best-sellers lists, but a lot and with the low overhead (the majority out of copyright and so free for the pickin' by any publisher so inclined), profitable. Someone is reading them, not just students.
You miss my point: We have precedent that writers who are too bound to their times tend to drop out of sight. Writers who have something to say that cuts across generations are less likely to, at least not for some time. And, of course, it's more complicated than that: Agatha Christie is quite time-bound, but we find her work quaint and fun even so, and adaptations by other media keeps her work in sight. Meanwhile, interest in Hemingway's work goes up and down like a yo-yo, one decade admiring it, another decade tsk-tsking his limitations. Faulkner, on the other hand, started slowly, gained cachet with the Nobel and is now considered not just an American author, but a world author, influencial on the development of the literatures of countries than his own in much the same way as James Joyce.
Randy M.