I think one of the commentators on the Scientific American web page linked to the Smithsonian.com link below said it best :
While bemoaning that the current generation’s music is inferior to the older generation’s music is a great American pastime, there is nothing minimally Scientific about it, and the editors would do best to avoid suggesting otherwise.
There is so much music being produced today, "pop" or otherwise, that the raw #s alone would make you think there is just as much or more great music being created today than ever before, even I you do believe the "signal to noise" ratio is lower.