There is nothing harsh about it (in its current form; for all I know GP may have edited something out). The author of the study deliberately and explicitly limited it to top-10 singles.
I think a much broader study would be less interesting in the sense that the top ten music reflects trends in popular music production. The long tail is probably harder to generalize.
This study says something about how many people consume music, or at least how the big peddlers want them to consume it.
noobermin might have read some anti-pop snobbery into my comment. I actually think pop is highly skilled. You don't just throw down some notes and vocals on Canon in D's chord progression and make a global hit. It takes real, skillful work in composition and sound design to make that happen.
I think a much broader study would be less interesting in the sense that the top ten music reflects trends in popular music production. The long tail is probably harder to generalize.
This study says something about how many people consume music, or at least how the big peddlers want them to consume it.