An Oscar movie trend I never understood...

I wouldn't say that it's anything to do with your age. I think some people just want (and produce) different experiences in films. Personally, I don't see it so much as being left hanging, but rather as a challenge to enjoy a film in a new way and/or for different reasons, like in NCFOM. One of my favorite things about movies is when the titles are either clever, or they carry a lot of meaning in regard to the true meaning behind the film. In NCFOM, the movie isn't really about the money or any of that. Instead, it's actually about Tommy Lee Jones' character, Sheriff Ed Tom Bell; his journey, and realization that things have changed since the good old days and that it is now, truly, no country for old men. That's why the film ends, quite powerfully to me, with him talking about his dream. You can see it set in on his face. He knows it. He's done. All that with Chigurh and Llewelyn is very interesting, and a fun ride, but when you watch the film with the intent on taking that emotional journey with Bell, it's quite a different (and IMO more rewarding) experience.

Now, does every film that "leaves you hanging" accomplish this? No, certainly not, but not everyone are the Coen brothers. Though, I felt Three Billboards did a decent job of it. Maybe not No Country level, but...

I agree for the most part. I don't know if it's actually a trend though. I see it as a misunderstanding of general audiences. The ending is the biggest opportunity for a film to leave the audience satisfied. Three Billboards felt like it didn't know a good way to end, and I honestly believe its lack of an ending is what cost it best picture despite having the most hype behind it. Hopefully it's a wake-up call to all artsy filmmakers to make sure they have an actual ending.

Even if it's ambiguous, you can still have a solid ending to the third act (Total Recall, Inception, etc.). Not sure I agree with your point on NCFOM. Shigur was built up as an ambiguous sociopath who gave people a 50/50 chance to live. It seems like letting her live would've been too bland, and showing him killing her would've been too dark. Did she even call the coin? It leaves the audience asking questions. The ending to Three Billboards wasn't nearly as interesting.

I don't think this movie ended with so much story to tell. I think that this movie is about the journeys and development of the characters. It's about Mildred's grief, so as she starts to smile again at the end of the film, we know she's moving onward and upward. It's about Dixon's awful behaviour and the fact that he's stuck in a rut. When he starts to pull out of that rut and act more selflessly and in a more self-aware way, well, we know he's moving up, too. Most importantly, it's about letting go of anger to stop those cycles and not allowing those cycles to control you. "I guess we'll decide on the way," and that's the end of the movie.

Now, as to why these movies are Oscar nominated (or winners) I think is because the kind of story that digs hard into characters, doesn't offer easy answers, and takes us on a journey other than the mainstream (mystery, solve the mystery, movie over) is attractive to the Academy. These are the kinds of things that people who love movies as more than entertainment or escape want to see: challenging movies, deep movies, maybe even profound.

It looks like they've left story to tell, but that's because we're trained by 90% of films to think of story as plot, but story is character first, plot second, and these movies are truly admirable for doing that.