I think you are and GP may be speaking of different types of people and motivations. Somebody who makes an outrageous claim and follows up to criticism or questions with "do your own research" is almost certainly full of poo.

By contrast people who do genuinely "do their own research" on topics tend to be pretty happy to share what they found, where, and why they think its significant. And they would love to be corrected if provably wrong, because its more of a lust for knowledge than anything else. And I think this is the sort of people our GP was talking about, whereas it seems you were talking about the aforementioned type.