Interesting, so one thing I would note is that the series starts with a fairly heavy setting presence. Geography and history are front and center. If a character goes to the east, or from the capitol to the north it's a journey and that matters. Later on the interpersonal action looms bigger, and things like travel tend to fall away unless they have some plot significance.What would you categorize Game of Thrones as? There is a ton of conflict and drama from the characters and their drives... but on the other hand alot of the setting creates and drives conflict and drama both dependently and independently of the individuals.
I'd doubt you could generate Westeros et al in detail as an outcome of zero myth play. I would imagine it more like BitD where the setting is substantially established, and it creates a milieu in which the game's themes play out.