The, in my opinion false, assumption you seem to be making the entire time, is that the encouragement is consistent for both forms — that it works the same for all people, both content creators and consumers. But there's plenty of people who excel at expression on either long or short form forms.

So I am _not_ claiming that articles or Usenet posts were universally bad — but a claim that they are somehow "better" than Twitter would be just as false. Especially in the case of Usenet. I mean, I don't know how rosy glasses you're wearing, but I do remember what it was like, and while not exactly 4Chan, it was often getting there.