Wait, why would an aggressive takedown procedure be favorable for advertisers? Advertisers just want popular videos on which they can put their ads, they don't care if the content is copyrighted or not.
Now, they probably care more about other types of censorship (for example, taking down offensive videos to avoid their brand being associated with them).
I think this is a good question. My suspicion is that the policy resulted from legal, rather than market forces. If that's true, then the fact that we the readers, viewers, listeners are the product sold to the advertisers is irrelevant.
Now, they probably care more about other types of censorship (for example, taking down offensive videos to avoid their brand being associated with them).