[dpark]

Impostor syndrome means that the person thinks of themselves as a fraud, not that other people do. So someone dealing poorly with impostor syndrome might well only chime in when they are exceedingly confident, or only when they do research and can be certain that the information/position they are providing is correct. If you keep your mouth shut except when you're 100% certain, you'll likely look like an "infallible expert" because you're always correct from an external perspective, even if you are quietly filled with self-doubt.

[charlesism]

Pretty much. Some people who lack self-confidence seem afraid to ever admit "I don't know" lest it somehow reveal their "fraud" to the world.