This law isn't directly attack 4chan you illiterate forgets. It's just banning Internet Anonymity. That doesn't mean you can't be named 'Anonymous' on a website it just means if law enforcement actually gave a forget they could more easily see who you are, as in you leave more information about your location and identity on sites.
I'm not saying I agree with it but Jesus Christ /b/ isn't a bad-ass legion of man-beasts, it's made up of stuffty immature 12 year old just like you all. And there are also a few neckbeards and people who have no social skills too, but that's notwithstanding.