Imposter syndrome is the belief that because you are capable of the virtue of doubt, you're somehow less prepared for the challenges of life than the many hubristic arseholes who lack the sense to recognize any consequences of their own poor judgment.
The world doesn't need more overconfidence. It needs more folk comfortable with doubt, of themselves, of their practices and institutions.
Questioning our ability or preparedness to do a thing is not the same as being unable to do that thing. Doubt is an invitation to play, the niggling joy in the challenge "Can I really do this?"