That's quite possible also. We also don't do long-distance airborne migrations, where the ability to innately determine your compass heading would be advantage

That's quite possible also. We also don't do long-distance airborne migrations, where the ability to innately determine your compass heading would be advantageous, since common weather phenomena like fog can easily hide significant landmarks from your view. On the ground, even if you can't see significant landmarks at a distance due to fog or low clouds, you can still use landmarks if you know what you're doing. Today we rely on compasses, topo maps, and sometimes GPS devices and altimeters to navigate when traversing trail-free wilderness, but there are still cultures that manage to navigate over long distances without such modern acoutrements -- some of them are so skilled at using methods like songlines (aka "dreaming tracks") that they don't even need to carry extra water, because they know where to find it.