Podunk people are indigenous to present-day Connecticut. The Podunk were thought to live far away, so living in Podunk grew to mean living in a remote, uninteresting place.

Originally, it may not have been used kindly. I wonder if Podunk could be thought of as an Americanization of the Roman's barbarians. (The others.)

What it means is this, if you are from a polity that has less than 10% of the global population nothing you will ever do matters. You are irrelevant.