Am I understanding right you're saying that a hallmark of modernism was good guys winning? That's very odd to hear--when I think modernism it's Hemingway, Joyce, Faulkner, etc, and they all wrote primarily huge bummers.
But that was before the 50s and 60s. So I'm not sure what the movement you're talking about is, exactly. That was the Beat Generation and postmodernism, which was if anything the real crest of alienation in writing. LIke--Howl and Sunset Boulevard and Alfred Hitchcock, and even light-on-the-surface fare like West Side Story very often ended with tragedy. There was a lot of raw material to reckon with--the Cold War was happening, WWII was still in living memory... hell, Blowup was 1966 and that was one of the most disturbing deconstructions I've ever seen.
Again, these are really long-lived, historically rich forms. We can talk preferences (and I think I probably agree with you there, being a fan of a nice HEA myself) without being ahistorical.
It's kinda difficult to explain because people like artists and philosophers rarely agree to what it means, but ...
The way I understand it, and I am not making this up, it's what I was told when I was wondering about the same thing, the modernist cinema (i.e. where the medium began) usually presents a certain set of values, and then advocates for this set of values as universally good.
There is no good parallel to this in the literature. It's about the film as the new, emerging medium.
It's why "good guys" win. Good guys win because they represent the certain set of "traditional" values, and the movie shows the triumph of those beliefs through the victory of the good guys.
Many westerns followed this format, with good guys winning because they represented the law, and order, and duty, and American way, or so.
Even war movies did it - the heroism, sense of duty and so on - was a prevalent theme in them, almost as Hemingway and others never happened. As opposed to "anti-war" movies, which, of course, did the opposite, and were more in line with Hemingway, and Joyce, and Faulkner, showing how cruel and largely pointless or even absurd that affair is.
The post-modernist cinema are movies like
Pulp Fiction, where not only there aren't any good guys that would represent any traditional set of values, and the plot is inherently cynical, but also the itself story itself is told in non-linear way so there is no traditional story structure with clear resolution.
Another post-modernist movie is
Monty Python (and Holy Grail) where nothing is taken seriously, not the story, not the message, not even the story structure, it doesn't even have a proper ending, because why take anything seriously?
