without being more specific, I doubt very much its the soundtrack. But if you watch some of the subjects being made fun of in this video by using their own works, Its not hard to figure out which side of the debate the complaints arose from.
I wondered about that also, but not from the perspective of whether Google would pull it for that, just from the perspective of whether it was appropriate. The same kind of questions I wonder about with regards to the Penn & Teller documentary series they produced.
I don't have any great insight on when it's appropriate to ridicule people or not and if any group of people deserve it, it would be the bozo's behind the 9-11 nonsense. Two questions:
1. Does the ridicule add to the entertainment value?
2. Does the ridicule add to the persuasive value?
With regard to question 1: When you are speaking to the choir it probably does. People like to hear there beliefs supported and counter beliefs ridiculed. And when speaking to the undecided there is a certain amount of humor from them because of the wit, but some of the ridicule was just straightforward name calling and probably wasn't that much of a factor with regards to the entertainment value for people without solid opinions on this.
With regards to question 2: I don't know. Candidly identifying the people behind this non-sense as ill-informed nut jobs seems like just a statement of fact to me and thus reasonable and persuasive to a degree. But the other side of that is that it is a bit off putting and makes the presenter seem a bit mean spirited and thus to be a person not completely credible.
Regardless of the above I think it is the single most persuasive piece that I have seen on this issue for a general audience. The detailed documentaries that I've seen are interesting to me because they deal with details of engineering and science while responding to the various theories, but I suspect that your piece would be more persuasive to more people about the idiocy of the 9-11 truther nonsense than the more mainstream documentaries.
As such, I think it would be useful to get the video in a form that could be consistent with U tube standards so that it gets a wider audience.