I think it’s not underconfident because our over-confidence is so high that it really is hard to be pessimistic enough to match reality. Depressed people seem to have just enough pessimism to compensate (but not overcompensate) for this bias. I don’t think that necessarily makes them have more common sense. Even just in terms of being more realistic, this is only one bias that they compensate for. It’s not like depression magically cures any of the other biases.
Depressed people also have a tendency to have an external locus of control, and that is not necessarily rational. You may not be able to control the situations you’re in, but it’s often the case that your actions do have a significant impact on them, so believing that you have very little or no control is often not rational.
I think it’s not underconfident because our over-confidence is so high that it really is hard to be pessimistic enough to match reality. Depressed people seem to have just enough pessimism to compensate (but not overcompensate) for this bias. I don’t think that necessarily makes them have more common sense. Even just in terms of being more realistic, this is only one bias that they compensate for. It’s not like depression magically cures any of the other biases.
Depressed people also have a tendency to have an external locus of control, and that is not necessarily rational. You may not be able to control the situations you’re in, but it’s often the case that your actions do have a significant impact on them, so believing that you have very little or no control is often not rational.