"I think people today who were born into a rock world, with all its assumptions about the variety of sound possible, and who haven't passed through that change, can have no idea what a catastrophic overturn it was. It is an imaginative feat to put yourself in a world without rock—"

Yes, rock has become a dominant form which nearly eclipses all others within the 'popular' musical genres. I suspect that for many people, of the last few generations, who don't have specialised musical tastes, if it 'doesn't rock' it 'doesn't compute'.