He sounds a bit resentful in the video that follows your video on YouTube.

He was being interviewed as an old man and told him story of how he wound up on the Woodstock stage doing that set. He explained how his opening F-U-C-K cheer broke the taboos and how his anti-war song was so different because it didnt blame soldiers when it was added to the Woodstock film later on.

Others ran with that broken taboo and made fortunes later on with adding the word to music and movies, while he was paid relatively little for breaking the taboo.