It's certainly worth keeping in mind the limitations that you describe and human's learning activity is certainly not as the rationalist intuition. But to take these limitation as entirely characterizing human activity seems bend the stick too far the other way and fly in the face of the many ways humans have modified their environment and adapted to those modifications and fairly often learned with only a few examples. And sure, plausibly a fair portion of those quick adaptation involve reworking basic facilities like vision. The whole thing is consistent with the neocortex sitting on top of the rest of brain and serving as a means to rewire it.