Music in the past 100-200 years or so has made steps both backward and forward many times. It rebells against the mainstays of the last generation and then rebells against the rebellion by regressing to the generation before that. It's a cycle.
You're probably right about that state of commercialism in music these days. Hell, most classical and some romantic era music was created just so that the composer could get by. So, YES, it was for the money back then too (although, the people who created this music also had their own side projects that they really cared about). However, the mass majority of popular music today is also commercialized (no shit). The music industry in the 20th and 21st century has not changed much in hundreds of years. What has changed is it's sincerity. From the 20's to the 80's, everything popular was unashamedly commercial in nature (from big band, crooners, popular rhythm and blues, to bubblegum pop, glam rock, etc). Starting in the 90's, a new trend started. The new, edgier revolutionary genres paraded about as being anti-commercial but ultimately diluted themselves by becoming mainstream radio mainstays (punk, grunge, alternative rock, indie, emo). The followers of these genres believed that they were going against the norm, and some still do. What is insincere about new popular music is that people think that they're music isn't "popular" and that they are making a choice to go against the norm. The music industry has learned how to harness this and pretend that their labels are "independent".
So it's all give and take. What we have in the past is unabashed commercialism with the occasional rare gem of a band that doesn't give a shit. What we have today is the regular part of the the industry that shoves pop down our throats, and the other part trying to fool us with new "different" bands that don't sound like anyone else (when, in fact, there are so many bands that sound like them and the only reason why we don't hear about them is that aren't picked up by labels). Of course, there are some gems today. But, in my own opinion, it takes some willpower to go out and try to find them.
On a side note, The White Stripes aren't progressive/avant-garde/different/etc . Everything that they've done just sounds like 60's/70's garage rock with blues stylings (no offense since I do like Jack White, it just gets old after a while). Kudos on the Zappa though, not many people can stomach much of his stuff.
S3C
<a href="http://newsimg.ngfiles.com/179000/179811_a_history_of_African_Ameri.jpg">http://newsimg.ngfiles.com/179000/179 811_a_history_of_African_Ameri.jpg</a>
"evolve" isnt very good word choice.
Psil0
Like the picture, but music in all honesty is truly always evolving.