Agreed, and I'd go further than you in saying that TEDx has a duty not to try to lead scientific discussion or research by presenting cutting edge information.

Agreed, and I'd go further than you in saying that TEDx has a duty not to try to lead scientific discussion or research by presenting cutting edge information. They rightly identify that they have a role as a credible purveyor of science, but lack the domain expertise to do more than popularize the scientific consensus. Which is fine: If they do nothing more than make the current consensus more easily available to everyone, that's a worthwhile activity in itself.