I'm in DC, and I don't support DC statehood. I'm running for President of the United States, not President of Lafayette Park. The Founding Fathers DID envision that DC would be a big town. That's why they put the Capitol a mile-and-a-half from the White House. If you don't like being a semi-citizen, it can't be more than 5 miles to a real State, where you have instant citizenship.
The overall effect on DC in this Amendment is they get to vote for all nationwide elected officers, President, At-Large Senators, and at-large Representative, and they get a tax break. And it stays a special capitol district appropriate to a nation of over 300,000,000 souls.