Of course, this assumes a model where one completely trusts or doesn't trust. In reality, you can read CNN (or Fox, or MSNBC, or whatever) and learn a lot of things that are true - you just have to figure out how to wash the layers of spin off them to surface the bits that really matter.

For example, I might trust that the news (not opinion) sides of CNN or Fox won't knowingly run stories that are actually false/made up, but I wouldn't trust any speculation or conclusions they draw, or that the set of facts they have given me are the most important or salient ones. This Youtube channel, on the other hand, is a completely unknown factor - I can't know what to trust about them, if anything, and it would be a big investment to figure that out.

Put another way: If CNN, Fox, the NYT, the WSJ, and AP/Reuters are all reporting something, how likely is it to be true? If only one of those entities gives me certain information about that story, how likely is that info to be true? And so on.