Web makes publishing cheap and easy.
Only a few short, non-Internet years ago, printing and widely distributing a publication meant having some combination of the right credentials or talent, the right connections or a just a big chunk of money. In most cases content was filtered by publishers, editors, proofreaders, teachers, librarians, buyers and distributors before it reached the reader. There's nothing new about self-published content of questionable credibility. Up 'til now, however, distributing such content widely always required resources available only to an extremely limited segment of society. It's all changed.