It can be a fine line. As I commented in another spot you have to gauge how far you’re pushing into another field. What I don’t like about the article is that it appears to put too much responsibility of the expert to stay in their lane so they do not accidentally lead people astray. Rather, I would put more responsibility on the layperson to question the methodology of a conclusion by the person making the claim.

When you’re debunking something, if your methodology is trust me, I’m a biochemist, that’s not good enough. It appears that is not what you do. It appears you try to understand things to the best of your ability, and your expertise may help you understand things a bit better that are outside of your expertise. I find it very obnoxious when someone will dismiss me because I’m not an expert, even though I have consumed a hefty amount of information on the topic.

One of my favorite examples of why you should analyze the claim and not the person, is the Wright brothers. In particular Wilbur Wright. No training in math, engineering, or physics. Never went to college. At that time, a betting man would have put their money on Samuel Langley, the scientist, the expert, and the Wrights beat him at a fraction of the cost. Langley became too focused on a problem that Wilbur saw was not a problem, and Wilbur was correct and focused on the correct problem that was keeping planes from flying.