Real physics argues that separation is the enemy. A wing stalls not because it "runs out of air," but because the boundary layer detaches from the surface due to an adverse pressure gradient.
For a sharp-trailing edge airfoil at a small angle of attack, the flow cannot physically go around the sharp corner. Nature forces the flow to leave the trailing edge smoothly, with equal pressure on the top and bottom surfaces at that point. understanding aerodynamics arguing from the real physics pdf