You make some good points Rhomal, but I don't think you painted the whole picture.
You're right that consumers would no longer buy hardcore rpgs anymore, but then, they probably wouldn't ten years ago. Despite being known as perhaps the greatest pieces of their genre, Fallout and Torment only had average sales in a time which we sometimes imagine as the second golden age of rpgs.
The problem of a lack of more 'pure' rpgs in the past few years has also been in part the fault of rpg producing companies as well. Interplay died out because of terrible management and multiple cancelled projects; Troika died because they couldn't get their act together. The result was a lack of 'pure' rpgs in the past years. How is this the comsumers' fault?
You also seem to ignore that there have been successful rpg titles recently, such as Morrowind and KotOR, or to a lesser degree, Jade Empire and KotOR2.
As for the future, I don't think it's as grim as many believe. 'Pure' rpgs will likely continue to be produced at the same rate they currently are, but something else will happen. Other games will begin to resemble rpgs more and more. We've already seen this is Thief, Deus Ex, and even the most recent GTA, but that's just a start. This trend will become increasingly common as developers seek to find something new for their games.