i suspect the appeal is the constraints. That you can tell a story and express emotion with 16x16 figures is an interesting counterargument to the "we need a trillion polygons per second to render a few hairs".
Erm, but do we always have to end up with extremes?
I think that pixelart games became somewhat of a cult at this point...
And no you don't need gazzilion polygons and GPU that requires private power plant to tell a good story - a while back I played Limbo and it was amazing.