If DC is pared down to the small area aroubd the Mall and the White House, do the residents of that tiny area still get three electoral votes?
I would assume that (other than the White House) the only areas that would be legally considered part of DC would be non-residential buildings, even if it meant that DC was this patchy area that wasn't a nice neat square.
And no, obviously normatively the President and his/her spouse and children should not have their votes count equal to 1.5 million people.