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.
