It's clear to me that I don't want to feel stupid
An interviewee just gave up in the middle of the coding exercise. He stopped and said "I don't want to do this anymore. This isn't worth it. This makes me feel stupid. And, I'm not. I know I'm not stupid, but this is making me question myself."

You could say that he gave up. Or you could also say that he chose not to work at a place where he would feel stupid. He chose to avoid an environment that wouldn't support him. As a coder. Or a human.

I don't blame him.

I have worked in agile environments with almost continuous collaboration. I rarely felt stupid. Someone was always there to support. To either lift me up or confirm that the problem really was tough. And we almost always felt productive. The practices ensure that you are almost always moving forward. They ensure that you are always working on the right stuff.

I have also worked at places that have shifted to an emphasis on individual responsibility. You get what you incentivize. Pairing becomes less and less frequent, then eventually reverts to "I'll sit with you just long enough for you to feel like you have an inkling of the solution". Discussion is virtually non-existent. In those environments, I feel stupid and slow a good portion of the time.

I'm not stupid. But, I am. In this environment, I am. And if output can be used as an indicator, everyone else is too.

It's clear to me that I am more likely to feel stupid, more often, when I am not collaborating regularly.

I choose to avoid these environments too.