best era of music would have to be classical. Even to this day it's still being played 400 years since its birth. Pop music and the rest are infantile compared to it.
Not to mention that bach, mozart, and the rest were geniuses in the music department, not just with playing a piano, or composing music, but how they were able to create truly original pieces of music way ahead of their time and some of which people considered radical. They were true visionaries.
Also, something about an orchestra of instruments in harmony with one another makes it more appealing than a clattering of drums and an electric guitar with a simple repetitive motif drowned out by some dude screaming into a microphone.