To further contextualize what I'm about to say, I'd like to clarify that I don't really differentiate different areas of music composition when talking about this kind of thing. So when you ask me to judge eras, I'm going to be including bands, composers, orchestras, and soundtracks for games and television.
With that out of the way...
The current era. Not because of the music itself:
But because we have such a stupidly, obscenely varied musical landscape with an insane amount of popular and indie groups producing all manner of music across a titanic variety of genres, styles, ethnic backgrounds, including mashups, entirely new genres or sound styles like dubstep or chiptune, on top of music made for wildly different purposes like dance, relaxing, general listening, accompaniment to stories and gameplay... all of this meaning more variety in music than ever before -- especially when you consider old-fashioned and retro style music still being made -- and is more accessible than ever through the various distribution platforms old and new and the internet in general...
And yet everyone just complains about modern music. >_<