While i do agree generally about key changes, i think the point is that it's just an example of something that sounds _interesting_. It's not just key changes, but all the little chances that an actual artist takes during creation, the things that sound good to some and bad to others are exactly what makes art, art. The change being witnessed isn't the loss of key changes, but the loss of everything that sounds different or interesting, in favor of a sound that is generally palatable to everyone precisely because it does not contain anything interesting.