Archival qualities aside, the best prints on fiber-based paper look much better than the best prints on RC paper. However good you are as a printer, your work will look better on fiber than it will on plastic across the board.

A more important point, perhaps, is the pride one takes in one's work. If a photographer is proud of his/her work, and believes in presenting the best craft possible as a means of artistic expression, then that work deserves the best possible presentation -- and that is on quality, fiber-based paper, well-printed, and archivally processed.