I'm surprised at some of the posts in here.
First off, white people have always been rebellious against authority. It starts when they're rebellious towards their parents at home, then at school. If they're teens and get stopped by cops they're disrespectful. They don't like being told NO...to anything. And short of murder the cops arent usually going to do anything to them, so their rebellion is only encouraged.
As they get older their hormones settle them down naturally, that rebellion still exists in their mind, but they don't have the energy or time to express it physically bc they have jobs, families etc . So then they start to latch onto ideologies. Someone is always trying to "take something away from them". That becomes the conservative cry, "they're taking our country away" , but then along comes the far right ideals of Trump(who actually is the king of I'm white, rich and do whatever I want) and voila, now you've created a moment where not only can they engage in their rebellion again, but they can take it to the extreme.
So yeah, while Woodstock ideals may have been liberal peace, the people there destroying were definitely the Trump supporters of now. And on top of this, you're putting aggressive music acts on the stages at a time when albums were selling millions of copies. Buying an album creates a different bond than streaming.