Yes I'd say so. I get where you're coming from but I don't think it's an excuse not to make decisions. Quite the opposite in fact.

I think of it like this: if you think you're smart, you expect to make best choice for every decision. So in tough situations, where there is no "right" choice, you beat yourself up about not doing better. If you accept you're stupid, you're willing to settle for the least wrong and accept failiure.

The same goes for interacting with others. Don't expect others to make the best choice, as they're stupid too, so you might find a better solution. But if you did not find one and they didn't, well, they're stupid, so of course they did not. Can't blame them really.

I'm no native speaker so perhaps stupid and smart are the wrong words in this context. Perhaps fallible and infallible are better suited.