Being asked to perform a complex task while someone else is both watching and judging you is way different from just talking through a non-technical interview. It’s an entirely different experience. Speaking a foreign language is hard, especially under pressure, but it’s absolutely nothing like trying to solve a brain teaser while the clock is ticking.

> I've seen no evidence that stage fright is a significant factor ruling out good candidates.

I'm just going to link again to a scientific study on the subject.

https://news.ncsu.edu/2020/07/tech-job-interviews-anxiety/

When you talk to someone you waste maybe 50% of your time/energy talking about what you do, meaning you effectively have 20 minutes instead of 40. Doubling the time you have available will make more people pass, yes, that isn't evidence of anxiety being a major factor.

Edit: Also looking at the data people spent more time on the problem in the private setting than the public. Their stats could therefore be as simple as the students not caring about the result and therefore they quit earlier in the more uncomfortable environment instead of doing it properly and checking their solution. This wouldn't be a thing in real interviews since there a lot is at stake so people wouldn't quit early, at least in my experience not a single candidate I've interviewed quit early.

Edit Edit: For example, their very impressive "All women in private completed it, all women in public failed" stat can also be described as "Women in private spent on average 16 minutes on the problem, women in public spent on average 7 minutes on the problem". Maybe if they had more at stake and therefore more stress they would have spent the entire 30 minutes and therefore done just as well?

Anyway, my point is that just because the abstract says they have clear evidence that stress is hurting performance these studies are still mostly garbage. Don't take it as proof just because there is a study.

Lots and lots of people have severe, physical, visceral responses to anxiety that can often be not only distracting but downright awful, feel-like-you’re-dying kind of feelings. This kind of anxiety response is entirely independent from day-to-day ability.

> Don't take it as proof just because there is a study.

I don't. I take my lived experience as proof that this is real.

You seem to be in denial of a common psychological experience.

Common sense is often wrong. I have very bad stage fright, I have went mute in front of class several times. I still don't believe it is a significant factor filtering out good candidates. It might unfairly filter out some mediocre ones though.