Right on. I strongly believe that if we do not admit something about ourselves, we cannot change that thing about ourselves. The most important skill I think I've ever learned in my life is to say "I don't know" often and unabashedly.

For me, saying "I don't know" was more of a social fear than an academic one. I thought people only liked me for my performance. But, like you, I learned that saying it didn't really affect the outcomes I thought it would, but it did result in learning a ton more. And I think, socially, it actually helped, because it humanized me to people who just saw me as "that super smart guy who gets good grades". I was no longer a machine they could not compete with, but a companion in the same struggle.

It's also much less exhausting just being true all the time, rather than trying to achieve some arbitrary educational or social metric.