|Click to enlarge|
As the graph clearly shows, at least in popular traditional fantasy: soft creators are bad, brutal ones are good. Possible theories:
A) Random Noise: There's no trend and this is just sampling error or something. Counterexamples welcome.
B) Jamie Lee Curtis Thesis (Grim Art Causes Empathy): Plausibly imagining terrible things makes you take moral choices more seriously.
C) Jean-Paul Sartre Thesis (Empathy Causes Grim Art): A person who takes moral choices seriously knows fantasy from reality and uses art as a place to safely explore dark feelings.
D) Art-as-Religion Thesis (Comfort Fantasy Amputates Empathy): An imagined world without terror or grey issues stimulates in the audience an expectation that problems should be able to be solved without reference to other peoples' needs or safety.
E) "I'm Baby" Thesis (Lack of Empathy Creates A Desire For Comfort Fantasy): A belief that the world is too horrible to handle so its ok to be self-absorbed also leads them to seek escape in worlds lacking in complex problems or difficult choices.
F) Self-Defeating Insular Fandom Nightmare Thesis: Note that creators on the cute end of the graph tend to be "from the internet". Grim fantasy has been increasingly ascendant in popular culture since the '60s and so many people who became successful in traditional ways ply its byways while safe fantasy as respectable pursuit is a result of the internet's refocusing on the aesthetics of underserved marginal communities (women and lgbt people looking for escape from a patriarchal world) but in addition to being more female/queer these creators are also more internetty and so reliant on internet communities--and internet fan communities are toxic and make people evil.
G) Inherent Profitability and Horizontal Competition Thesis: Either because they are inherently more dramatic thus appealing thus profitable or because that's the current public taste and thus profitable, grimdark creators make more money and don't exist under as much competitive pressure as creators doing comfort art. The comfort art creators are fighting over limited space and so do terrible things.
I have no idea which of these, if any, is accurate.