I think we need to look at that carefully - especially, how much of youtube hate is well-considered, articulated positions and how much is people just "swept into the propaganda." That's a complicated question but think the medium of video tends to be worst form for well-considered opinions and the form most likely to just be a carrier of irrational-emotional/progandistic messages. It's real time stream of imagines/words quality makes it hard to consider the logic of an argument and easier to get swept up in the emotions of a claim as well as easier to think that, say, an image of a scientist gives legitimacy to a claim,etc. I think this quality was demonstrated back in the days of TV as mass medium.