Most of the popular music we listened to was crap. We just look back on the past with whatever the acoustic equivalent to rose-tinted glasses could be, and forget that crap when we remember the gems. The same goes for our parents, and the same will apply to the youth today.

That said, I can see a flattening of music. Dynamic range seems to be fading. Instrumental variety doesn't seem to matter. There aren't any real quirky subgenres making it big like ska and grunge did in the 90s. There doesn't seem to be an equivalent to hair metal arena rock from the 80s. For all its flaws, disco in the 70s was different.