There's no "guarantee" that links submitted to reddit or digg will be seen by a significant fraction of people, either.
As for the submitter's need for popularity, I think the basic problem is that you need to find the right way to balance voting on stories (which should be more or less independent of a story's popularity, as the article argues) with viewing stories (which must be inherently based on some notion of popularity or story quality, or the whole point is lost). That seems like it should be solvable, though: for example, you could present both kinds of items in the UI.
As for the submitter's need for popularity, I think the basic problem is that you need to find the right way to balance voting on stories (which should be more or less independent of a story's popularity, as the article argues) with viewing stories (which must be inherently based on some notion of popularity or story quality, or the whole point is lost). That seems like it should be solvable, though: for example, you could present both kinds of items in the UI.