To me, one of the things that makes Dark Fantasy great, is it has an appeal to those who've lived lives of hardships, poverty, double standards, or otherwise lives that could be more pleasant. As I have said before, due to my high functioning autism, and the fact that I'm a male to female transwoman, my life is similar to that of an Elf on Thedes. I'm seen as the other, my view of morality is very different to neurotypicals, I get punished for things that neurotypicals get away with, and am scapegoated for crimes those in power do or have done. So I can immediately identify with both Dalish and Cities. Though I'm a Dalish fan because I'm proud of who I am and refuse to conform to double standards.
Outside of my own life, I can see an advantage Dark Fantasy has over High or Heroic Fantasy. Being able to handle tragedy and disaster. I love High and Heroic Fantasy as well, but I've noticed that in some of them, characters can't take tragedy and disaster well. in two of them, which I won't name because of rules, when two characters and races who are supposed to be paragons of goodness and mercy, suffered a betrayal among their people, they reacted with reactionary, anger, and began resorting to more brutal and less methods of handling threats. I've seen similar things happen to people who are good people, but suffer or learn of terrible things.
But this seems to be rarer to Dark Fantasy. This makes me theorize that if you live in a Dark Fantasy world, characters are better prepared for the worst things to happen, and can find ways to resolve them without sacrificing morality, which leads me to the ultimate reason why I think DA outclasses the rest. Sorry it took some paragraphs to get here, but I needed to make sure you understood one thing before you can understand another.
But there is a flip side to this coin. A lot of Dark Fantasy falls into a unpleasant writing trap. A lot of Dark Fantasies come with morals that are presented as wisdom, but in truth, will do more harm then good, regardless of the life you live. And that moral is, "In order to survive in a world that is dark and cruel, you need to be dark and cruel." This is why I didn't like the Dark Fantasies Berserk and Akame Ga Kill!, and God of War. Because those stories teach that you should be unkind, that you should not trust people, that kindness and compassion are weaknesses that will be repaid with violence and treachery, and that violence can only be answered with more violence. That violence is strength. That hurting others is not only enjoyable and desirable, but it should be employed first when dealing with threats. And the grand messages of those stories is "If something bad happens, be sad, be afraid. Then give into that sadness or fear, and embrace every dark, sick, and inhuman part of your soul, and do everything to them that they will do to you. I think the reason that so many Dark Fantasy heroes are written this way, is to give audiences something they can take their frustration or rage on without any moral questions.
But in Dragon Age, that's only one option you can follow. Some fantasies, including Dragon Age, the Diablo series, and even Game of Thrones of all things have different approaches. They acknowledge that while their settings are dark, full of war, monsters, oppression, and other hidden terrors, it's not worth lashing out nor are they always defined by cynicism, or cynicism has a "do not cross" line. Though how common they are varies, we see acts of kindness being highlighted and moments of humanity. We see people bonding over their fears, losses, trauma, and hardships. After all, sharing your sadness to others is a sign of emotional maturity, not bottling it up. Characters in these kinds of Dark Fantasies teach themselves to not become their enemies, and to find ways to go on when the worst things happen. Hell, sometimes they create gallows humor like jokes to cope with it. This is a unique form of goodness that can't be found in any other kind of fantasy. This is because in some ways, these characters are creatures of the dark, but dark is not always evil.
And true, sometimes these characters do get revenge or payback. And many of these heroes still have some dark fantasy traits. Some are anti-heroes or knights in sour armor. Some have depression. Some get drunk at times, others like to visit brothels, etc. But unlike the stuff I've mentioned earlier, those are not abused concepts and the writers know that even characters like these have rules to follow. But it's rarely done in ways that seem reactionary, angry, or brutal. These heroes know that different villains must be handled in sometimes different ways. I've even seen some Dark Fantasies where heroes show mercy and sometimes even forgiveness to villains a High or Heroic Fantasy hero might kill without a seconds hesitation.
In hindsight, Dragon Age presents a different grand message, which you can choose to follow or not. "Look for good in darkness, and you'll find a form of goodness and empathy you may not find anywhere else. Remain on the side of morality, even if the whole world tells you it's wrong. And when you stare at the darkness, never blink."