Why do old people complain about music's decline when their generation is clearly the one that cheapened music?

I think there's a place for "simple" music as much as "complex" music. After all, who's to say what is appealing to another's ear? I have a world of respect for a "complex, thoughtful progression", however, I also have the same respect for a talented musician who can make only a few chords sound amazing by virtue of their technique. I think the identity of rock music is more the attitude with which it's delivered rather than the complexity of the music itself. I would say commercialism & m-marketing play the biggest part in the "cheapening" of music, and I always keep in mind that performers can do their thing without critics, but it doesn't work the other way around.