And the South was not under control of the US, so it freed no one, technically.
Inaccurate, technically. Large areas along the Mississippi and the southeast coast were occupied by the Union military, but not excluded from the Proclamation. So slaves in those areas, 50k to 70k, were freed immediately.
More critically, as Union armies advanced, wherever they went the slaves were freed. It's kind of stupid to claim that the Emancipation Proclamation freed nobody, since when the war ended it had freed somewhere in the vicinity of 3M people. That this took two and a quarter years to implement fully does not change the fact that it happened.