There have been recent music festivals, bigger than Woodstock:
https://www.28degreescard.com.au/tra...the-globe.html
https://www.bbc.com/news/world-44697302
Woodstock 2011 Poland, was said to have over 700,000 people.
Watching the documentary in the OP, it was a miracle that Woodstock was not a huge disaster. They had to change venues with 3 weeks remaining and were totally unprepared for the number of people that showed up.