[Do we have legitimate governance, with the consent of an informed electorate?]
That's a fascinating question.
We've come a long way since our origins with the vote only going to propertied white men under the supreme law of the land, the Constitution and federal legislation. If we function under a common law or an objective standard for what is legitimate then yes we have legitimate governance as it is based upon written standards that are democratically determined (or rule of the majority). Under our system of governance, decisions are based upon bare popularity not informed popularity. That is partly because we rejected past concepts like Britain's "unwritten" constitution and laws and subjective standards it bred.
This also applies to civil law that runs contrary to predictability/uniformity.  We have a difficult enough time making political decisions without accounting for changing language and social mores on "informed"/safely empowering those who get to decide what is or isn't.