From another one of your comments:

> I'm arguing that you can probably have both -- by using human moderators.

I don't think human moderators can review 720K hours of video per day. (on YouTube) You would need to hire >100,000 moderators to continuously watch videos all day and have some redundancy in reviews, then 1,000s of supervisors to make sure moderators are doing their job correctly. (almost impossible when you review videos all day with no break) Let's not even get into comment moderation...