What do you feel about the pseudo arms race in the grim-dark movement that's present in a lot of literature lately?
I'm not necessarily an expert on this subject, but I'm assuming that this is about the constant presence of how everything in literature (from YA to other genres) has so much grimdark (read: dystopian and post-apocalyptic) themes and structures. Personally, like with anything else that gets overexposed due to the success of something else really needs to be toned back, because authors will either way to piggyback from the success of another franchise, or feel like they aren't really making the effort in the world-building and actual structure of a good story and just going for the repeated themes. It's similar to how a lot of fantasy writers try/have tried to copy Tolkien, they just want it to be the "next big thing" rather than creating a good story. Oversaturation of this sort is so overwhelming that it becomes underwhelming whenever a new series comes out that is very similar to what a previously marketed one was.
I actually don't mind grimdark in the general sense just as long as it is well-written, has an intriguing and well-structured story that makes sense rather than simply being there because it is what it's expected from the subgenre, or what they think the subgenre is supposed to be.