I’m going off what was in the movies and other than Coruscant there’s nothing to suggest there’s that many individuals. There are a lot of representatives in the senate but that doesn’t say much about how populated the planets are.

And, the Jedi had an actual HQ on the home planet of the republic, didn’t they?

EDIT: And as another counter-example, there’s not that many Secret Service agents but most people in Earth probably know they exist.