I will be honest, I couldn't even finish watching any of those videos. The guy is such a douche.
First off, out of the millions of people who comprise Anon, there are only probably a few hundred really talented hackers. And even if 4chan was shut down, they would still be out there.
Secondly, the stolen passwords were 99% guess-work. People are complete idiots and will put their password as their fucking
name. The other 1% is 99% from phishing, which is easily avoidable if you aren't a complete tool (the 1% of the 1% are keyloggers, which are transferred via 3rd party sources and can't be pinned on Anon, but rather you yourself because you're an idiot and will download anything free from cursors to backgrounds to emoticons).
Thirdly, Anon doesn't kill people. -_-
They may be racist (although most of it is just a joke), and they may be perverted (or at least more vocal about it... plus graphic illustrations), but they don't pose a significant threat to your life.
If you get driven to suicide by a group of Internet-whores pointing out your faults, on the other hand, then the gene pool was better off without you.
The FBI has tried a number of times to shut down 4chan, which indicates that Anon is simply gross and not a real threat. A real threat would be kept a close eye on, and it's not like security is tough on 4chan. An annoyance would be shut down, or at least been targeted by an attempt to shut it down.
You want to bring down /b/, unite with the people who occasionally DDOS attack it. It's the only way to affect Legion.