You need to understand the economic incentives in operation. Advertisers and Google have a risk avoidance incentive. It doesn't matter if they pass up good ad

You need to understand the economic incentives in operation. Advertisers and Google have a risk avoidance incentive. It doesn't matter if they pass up good ad friendly content. They definitely don't want to take a chance to put their brand in front of ad unfriendly content. Now unlike television where ad inventory is limited, on the internet, it's a buyers market. Even if the advertiser passes on something potentially good, he can always find some other content to place on. Indeed what he is buying is actually access to the people watching content, not the content and since the same people on YouTube will probably watch other videos as well, why not de-risk by automatically screening out everything potentially controversial?