Well, whilst it is clear from the Cambridge video that the air doesn't meet again at the same point after the trailing edge of the wing, it is also clear that almost no air is deflected downwards - the streamlines only a short distance below the wing are completely undisturbed!
How does the Newtonian 'deflects air downwards therefore produces lift upwards' school of thought explain that?
The 'flat plate' effect at least is understandable since it relates exactly to what happens when you stick your hand out of a car window - the air pushes against your hand and forces it upwards.
I have yet to listen to the whole of the video RVDT has posted but the first 10 minutes are not that enthralling - he tries to rubbish benoulli lift theorem by saying that an aircraft in a 2G turn doesn't increase its speed so it cannot increase the acceleration over the top of the wing - I don't think he has heard of angle of attack.