We evolved to share information through text and media, and with the advent of printing and now the internet, we often derive our feelings of consensus and sureness from the preponderance of information that used to take more effort to produce. Now we're now at a point where a disproportionately small input can produce a massively proliferated, coherent-enough output, that can give the appearance of consensus, and I'm not sure how we are going to deal with that.
