I can't say that music has gotten better, but neither can I say thatit has gotten worse. There are plenty of great bands and artists that emerged in the '80s, '90s and past the turn of the century. Talking Heads is one of the very best. Bob Marley, Springsteen. The Pixies, John Spencer Blues Explosion, Morphine. Adele. Jonathan Richman and the Modern Lovers, who has been around since the early '80s, but I never heard of until last year. Gogol Bordello. Some of these will last longer than others. Johnny Cash and Dylan have persisted through the decades. The American series, six albums of covers that Johnny Cash recorded before his death are some of his best work. Plus, we still have all the old music. Hank Sr., George Jones. If I get sick of what is on the radio, I can fire up some 1959 bebop, Oliver Nelson, Freddy Hubbard, Monk, Coltrane, Miles Davis. If I want to reach back a little farther, I have hours of Django Reinhardt on my Itunes.
My boy still listens to the stuff I played when he was little, that goes back before his time. Lou Reed, Bowie, Cowboy Junkies, Elvis, Leonard Cohen. In turn, he and his friends have introduced me to tons of music I might well have missed.
I see no point in discussing whether music has gotten better or worse. We have it all. You don't have to listen to it all but you can find great music from any era.