Blame it on the audience
My first note in this movie review is one for the audience. If you're not a native or good English speaker, you will miss even the fact that the film's title also refers to said protagonist. In the sense that he is green, inexperienced. Not just to the mystical apparition that throws the challenge to the Knights of the Round Table.
A challenge that is accepted by the young lady's man, Sir Gawain, King Arthur's nephew. Who, lacking in any heroic deeds to speak of, seems himself obliged to depart on a mission whose finale is already established - the chopping of one's head! Now I'd like to not say anything more about the script. I will leave it to you to deconstruct the message for yourself. Because this too is an endangered art, in a cinematographical way of speaking, at least.
And I see a couple of problems here. First, we do not want to do this. We only desire rapid gratification entertainment. And secondly, we also chastise any new types of presenting a story. In the case of The Green Knight, it's quite simple and has been done many times before - the young knight who goes on a quest of self-discovery, for courage and honor. The main theme here is the hero's journey.
The typical monomyth
In his adventure, he meets diverse characters, more or less dead or moral, human or beast-like, all towards the purpose of testing him. The primary gist of the movie is that the protagonist fails in a big way. So, not being a classical format type of movie, the outcome and moral of the story are also certainly different from what you'd expect. It's about failure, shame, and the loss of honor as opposed to the gaining of it.
You really don't have to be a genius to figure that out as much. Although it would help if, in the past, you had made an exercise of sometimes thinking in parallel, in abstract, obscure, metaphorical directions, even in nonsensical ways. It is your right not to do that, of course! But it is also your loss and, in all actuality, everyone's loss.
Denouncing the weird and propagating only the familiar truly is to the detriment of the consumer. The one who sells will push the superhero genre movie endlessly, and the ones like the one on today's microscope, bold and out of the ordinary, will disappear.
A 14th-century chivalric romance
If we Google around after we see the movie, we also find out that it is based on the Arthurian story Sir Gawain and the Green Knight. Perhaps the movie is not a perfect adaptation of this rhyme-y fourteenth-century story. But the effort alone deserves praise. And the fact that you can continue doing research and understand more after you're done watching, in the sense of general knowledge, adds to the experience. Of how many modern movies can you say this?
This movie reminds me of crazies such as Holy Motors (2012) or The Lobster (2015) and, to a lesser extent, Coriolanus (2011), The Imaginarium of Doctor Parnassus (2009), or even Birdman or (The Unexpected Virtue of Ignorance) (2014). So, if you thought any of those were good, you know what to do.
