So the whole point of the documentary seems to be that rock and roll was/is a business that sells an ideology of peace, equality and non-commercial values, but...when people begin to take this ideology seriously and expect the performers to do so as well, there can only be a conflict due to the hypocrisy created by commercializing ideology.
Rock and roll is the business of selling ideology and those who help sell it get to live comfortable lives pretending to be something they are not.
So the rock performer starts off among the people and criticizes the status quo. If he/she is really good and successful he/she gets to join the middle or upper class of the society he/she criticized. So instead of the music being used as a tool to change things, it becomes a tool of upward social mobility for the performer.
The performer in this film is seething with elitism and arrogance. She relates a story of how she was at a Hopi snake festival and thought everyone else there was a tourist. My goodness, I didn't know that Joni Mitchell was a Hopi Indian.
She often refers to the crowd as a beast. To me they looked like young human beings looking for inspiration and poetry and they reacted negatively to seeing a huge fence that had been created to exclude people so that rich performers could become richer. These young people could sense that something was wrong.
This performance is about someone who is in complicity with the whole shady business of rock and roll, is forced to face that temporarily, but who recedes back into denial as she woos and quells 'the beast' with her musical excellence so that they, themselves, no longer care to think about what is really going on.
You can see this highly ironic film right here:
https://www.youtube.com/watch?v=b7IYpfPr7ow
