I'm going to go with the the Vaporwave genre (and related). Such wasted potential. Maybe I had high expectations, or my idea of what it should be is different than what everyone is doing with it. The "nostalgia" factor really pulled me in, even if it was often a sort of postmodernist critique of consumer culture. I didn't see it that way though. I thought it was pretty great that people were making music that made use of sounds that, at least for me, brought back memories of life in the late 80s and early 90s often without referencing anything directly. And somehow it still felt fresh. Fast forward a few years and it's as though everyone is just going off of the same template. The same general sound, concept, and imagery.