For some reason this idea of "stand the test of time" always bothers me - I like that 80ies music sound so different from 70ies and 90ies music and I still love to listen to Thriller, Tarzan Boy, Cruel Summer, Princes of the Universe, Piano in the Dark etc. But there was also a ton of crap music in the 80ies just like there is now and in every decade. We just tend to remember the good stuff.
I don't think music (or books, movies and games) should be made to "stand the test of time" but should be enjoyed NOW! So maybe we will not remember some tunes 20 years from now that we enjoy today but so what? Taste can change and what we enjoy today, we may hate tomorrow. It's great that we remember Elvis, Mchael Jackson, Beatles and Madonna but I also love finding a song (or game, book, movie) that everybody hates or don't know about and then just loving that song in my own special way - just for the sake of pleasure.