I think you missed it, Doug. I remember this passage only because it was a huge disappointment to me. I used to like rock (and still do, despite what you may think) and expected a better treatment of it in a textbook on music history.
My cultural attitudes that you lament come not from liking or disliking any particular genre, but from the way music is reproduced nowadays. We are inundated with attention-grabbing clues, both visual and aural - "look at me, look at me: more! louder! flashier! better! more outrageous!" - and after a while all you want is peace and quiet, a void, a time to pause and reflect without being constantly bombarded with visual and aural stimuli engineered to grab my attention.
I realized that for the first time some ten years ago, on a train from Los Angeles to Chicago, when after spending some time in the culturally overstimulated LA I woke up early in the morning in the desert near Flagstaff. The Zen-like aesthetically minimalist experience of the desert was stunning and also revealing the overstimulating quality of the manufactured art and culture.
In short, it is not the content of the message but the glut of information. It is like with spices - they enhance the quality of food tremendously if used in moderation, but render the same food inedible if used in excess. It is all about balance and moderation - concepts that US-ers lost many years ago to marketing hype. At this moment, the only way to maintain this balance is to filter out most of the noise generated by commercial culture.
Wojtek