Maps like these make more sense in traditional RPGs. Because think about, in the first FF for instance, it gave you a sense that you could explore, but in reality it was linear, and there would be stupid things blocking a path, like a broken bridge at the start that the king will have repaired so you can cross, aka, do this objective and you can press on. By having other obstacles like mountains and what not blocking the path instead of broken bridges and the like, it takes away the annoyance of, "Hey look! A free open world! But you can't explore there until that bridge is fixed. Oh, sorry, that cave has collapsed, but do this task and MAYBE it will just be fixed up, and ready to explore."