I was a tween when the first version of “punk” came around (yes, that makes me old). I think I can say with authority that the ideals were: anti-corporate, anti-consumerism, and anti-commercialism. Ever since then people have tried to sum it up (and marginalize it) as “DIY.” But that falls well short of what it really was.
Of course, the second it showed any sign of viable popularity, the forces of capitalism, well…, capitalized on it. The obvious examples are bullshit, high production, made-for-tv bands like Green Day getting sold as punk rock. But does anyone remember Urban Outfitters? Holy crap, the open, unashamed corporate pandering!