One critique of three-act structure is that the idea is self-perpetuating. Because there’s an industry of books about the subject, aspiring writers are likely to format their work in this particular way, even if it isn’t otherwise advantageous. George Lucas has been open about the fact that he copied the monomyth from Joseph Campbell’s Hero With a Thousand Faces for Star Wars. And when that film made a lot of money, you could bet that studios were interested in repeating every element about it that could work.
A studio’s readers, who decide which scripts to turn into movies, might also be brainwashed by the idea of three-act structure, and thus be more inclined to select screenplays which conform. Aspiring writers aware of all this will also be less expected to stray from the usual format. The most dedicated wannabes, the ones who have done the research and are thus more likely to succeed, will also be encouraged to go with it.
Robert McKee charges $785 for anyone interested in attending his seminar. That includes many professional and aspiring writers. In the last year, he has addressed sold-out crowds in New York, Los Angeles, Montreal, London and Seoul. He has spoken to tens of thousands of wannabe screenwriters, all of whom have chosen to invest in improving their craft. Some will go on to write screenplays good enough to be made into films, so McKee might simply get credit for their success, even if it was going to happen anyway. They might do well writing three-act screenplays, but it’s possible that they would have done just as well without that.
I have a small amount of insider information here. Several years ago, I took a brief class on writing for comic books taught by then-Marvel Comics editor Andy Schmidt. He was a big fan of McKee, and noted that the company paid all of its editors and writers to go to McKee’s seminar. Since then, Marvel has branched into film, producing adaptations of their characters. And those movies tend to abide by three-act structure.
So there is certainly something to the idea that people are rewarded for following the structure. Though it’s unclear if that’s because the people in charge are brainwashed by the feedback loop, or because the experts have come to the conclusion. after a tremendous amount of research, that this particular story form works especially well.