Imposter syndrome is our natural social/emotional protection against 'knowitall' syndrome where you speak and act confidently when you are unqualified and mislead people. The ability to speak and act confidently is a learned social skill, normally you are supposed to learn it by peers validating/respecting you/you respecting yourself. But the process can be shortcut by imitation and 'faking it till you make it'(e.g. The type of confidence sales people tend to have doesn't run as deep imo)