Me, I listen to what I want to listen to at any given time, and don't much worry about what proporton of the reason is "nostalgia" and what proportion is "quality" (surely both are involved in many ways, as are many other factors at other times, like "trendiness"). If I'm enjoying it, I'm enjoying it. It's my collection, my time, my enjoyment. Bit of a silly argument overall to me, and pretty elitist/snobby.
Nostalgia is ok until it stops economically to develop current music, the popular music scene here is invaded by young singer and artist , talking about fm radio, doing (quite often very bad) covers of songs done in the 60s and the 70s , if you add the mix of real retro songs put in the mix, there is little time to give airplay to new songs created today.
But on a personnal basis there is nothing wrong with it.