Though I do see why people don't think such fondly of Blade and Soul, I do think it's unappreciated.
Since this is an adaptation of a game, the makers probably chose to focus on the characters than the war.
While I do see the show lacked on the world building department, on characters development department was top notch, specially on the MC.
Aruka started as an empty character, moving only by the desire to kill her master's killer. And that wasn't for revenge, at least, due to her lack of emotions, it seemed that way to me.
But during the course of the story, her evolve at a slow but extremely well built pace. The other characters also had great development, Karen in particular.
But, it all culminates on the end, when someone ask her what she was doing and Aruka answered "living".
The story could be seen as an unique genre of it's own. Almost like a Action Fantasy slice of life.
I'll say again. I do see why people complain about Blade and Soul, but if you watch thinking about the characters and how they evolve with each chapter, maybe people would appreciate more. Or perhaps this is only wishful thinking.