What has been denied?

"All of this ink and time being spent on giving the residents of the District of Columbia a 'full voting representative' in the House of Representatives. What exactly have the residents of the District of Columbia been denied as a result of not having such a representative?"

Simple answer: They have been denied their inalienable (innate, inherent, intrinsic) rights as citizens of this nation to participate equally in this participatory form of government which all other citizens enjoy. They are Governed Without Consent. They seek Equality, Nothing More, and will settle for Equality, Nothing Less.

They are denied recognition and respect for their inalienable right (which cannot be sold, traded, or taken away, an arbitrary, anachronistic, and artificial provision of the Constitution notwithstanding) to Consent to the laws under which we all must live, to be heard in the national consensus which we develop via our national legislature.

Denying DC the opportunity to either grant or withold Consent over the laws under which we all must live (as exercised by all other citizens in the fifty states) leaves the power exerted by Congress over the District both illegitimate and tyrannical. Recall that our Constitution, as originally written, denied these same fundamental rights to blacks and women, too. We have corrected that over time as we strive for "a more perfect Union." The task is not yet complete.