On the 737-Max at high angle of attack air flows from over the top of the huge engine cowling and continues to flow over the top surface of the wing due to its location in relation to the wing leading edge.
Had the engine been located lower this would not happen - air would slip bellow the wing. Having been located so high it becomes part of the wing lifting surface far ahead of the wing itself.
That moves neutral point towards front and reduces static stability margin.