They've 7 outfield players behind the ball when VdV wins it. You also have a massive gap between Dalot and De Ligt that VdV strolls through. Man U were anything but compact.
I'll take your word on their game plan but I didn't pick that up from watching the game. I struggled to understand exactly what they were trying to do. Even on the second goal, we end up with 4 against 3 or 4 of their players. I'm not taking away from how good we were but if United were trying to be compact and play counter attacking football we'll encounter teams this season that do it a hundred times more effectively. Those games will be a better test of where we are under Ange.
Their plan was to play a mid block in a 4-4-2, a few analysis post game go through it, a few big issues
- Front two basically were too far from midfield 4, left Bentancur constantly open between the lines
- Front two didn't press (didn't have a trigger to press), that allowed our back two to consistently get the ball to Bentancur or FBs which (because their front two were so high) instantly created an overload behind them, that Overload then passed on.
- We also (see diagram in match thread) pressed so effectively it killed their ability to counter (they either had no pass on or we intercepted lots)
United has been one of the best counter attacking teams in the country under ETH, it's literally the only thing they have, that's why they have 2 FA Cups and have actually beaten good teams.