Ron Silliman argues that the originality of the more original "post-avant" poets wears the mantle of trobar clus - total "engagement", poesie der poesie, as opposed to more watered-down or populist efforts. He's saying that the really good poets perform the really hot stuff for their peers, for the cognoscenti; no one else will get it.

Nice responses in the comment box from Larry Sawyer & Michael Peverett, who brought up Parzival.

My motto is : Ars Est Celare Artem (Art Is To Hide Art). Poetry can exhibit complexities of communication and motive, but hermeticism is not a requirement for their accomplishment.

In fact, I wouldn't be surprised if there is a direct and reciprocal relationship between originality (&/or technical innovation) and reaching wide audiences. Sometimes. Not always - think of Gongora or Mallarme. But sometimes. Think Whitman, Shakespeare, Dante...