Putting myself in that situation... I imagine if I was confronted at random and given a few seconds to give my opinion on a subject I know nothing about, but my social standing would gain more by my saying something than by saying I know nothing, I would absolutely say with confidence an opinion.
It would be wrong, probably, but I would flash a smile at the interviewer and make an effort to both appear genuine and be totally forgettable.
That's a bit harsh maybe? I'm not sure it's all about self confidence per se. Your mind can play tricks on you. Do you go around assuming that people you meet are lying to make fun of you? Is that thing they're mentioning the same as that thing you were reading about a few days ago? Is it lacking in self confidence to assume that it was, or to assume that it wasn't?
Regardless, at some level, it points less to self-believed knowledge, as is the premise of the article, and more to socially pressured self-presentation.
Everyone on Jimmy Kimmel who went home and thought to themselves, or told their significant other "I didn't know what they were talking about but went along with it" is contradicting the premise of the piece.
These experiments / "experiments" tend to involve a significant factor that would invoke bs'ing. E.g. being interviewed on camera from a crowd - saying "uh" and "dunno" instead of answering is guaranteed to get your clip cut. Or in a scientific experiment: our society values knowledge. So if your amount of knowledge is being measured, a natural response would be to try to look extra good.
If they did am experiment like this, informing everyone a priori that some of the statements are bs, and that at the end, they're graded on identifying the bs as well as their knowledge, that could lead to a different outcome. At least it's one way to somewhat mitigate the desirability of appearing knowledgeable.
It would be wrong, probably, but I would flash a smile at the interviewer and make an effort to both appear genuine and be totally forgettable.