While this is a point worth making, another is that there's also little to no vetting or editing required to publish "information" on the web compared to getting it into a book and into distribution.
Of course the latter isn't perfect and comes with its own evil hegemony and other assorted issues, but the point is that there is so little barrier to entry to posting on the web that praising speed in and of itself ignores relevant and important issues.
Fair point, but I would argue that "known" and trusted organizations, such as Khan Academy or Coursera, backing a given instructor or set of materials constitutes a form of vetting. It's not like they pick their material out of a hat, and they're all fully aware of the potential repercussions of publishing quackery.
They were here for such a long time, way before anyone else and yet they are practically forgotten now. I wish it had been given the attention it deserved by the good folks at MIT.
By the same turn, it's also much easier to propose and make corrections. If I discover an error in my computer graphics textbook, I'd have to...call the publisher and see if they can fix it in the next edition, I guess. Perhaps the textbook industry's fixation on keeping students buying the newest editions of their books has actual benefits...
Of course the latter isn't perfect and comes with its own evil hegemony and other assorted issues, but the point is that there is so little barrier to entry to posting on the web that praising speed in and of itself ignores relevant and important issues.