Part of writing my game has been trying to make it setting neutral, so that (for example) races don't do anything, because a GM may want to make their elves the usual tree-huggers, or may want to make them flesh-eating cannibals or fey with a completely alien morality or whatever instead. A ruleset where elves have a bonus to hide in forests or dwarves gain the ability to see in the dark and understand stonework creates an implied setting: mechanics that effectively state the way things are...
