You're ignoring GP's "busting their ass" observation, which is probably key to this. No-one is going to hire someone to write or direct a movie based on their having a degree from some institution. It's either going to be because of their track record in the industry (because they busted their ass at the start of their career and had some lucky breaks) or because they have the right connections (so, nepotism). So I'd say GP's observation is right on the nose. Some successful filmmakers may have an undergraduate or postgraduate degree in a relevant subject, but their success in the industry has almost nothing to do with that qualification. Which raises the question of why anyone in their right mind would pay Columbia six figures to get such a degree, especially since their own faculty appear to be industry failures.