Witness the 'thumb' of a panda, which is uses to strip leaves from the eucalyptus branch. It has a thumb (toe on its paw) but no, evolution chose to extend a wrist bone in a kind of protuberance; the panda pulls the branch between that and its arm to strip leaves. Not ideal; kinda weird really. But evolution doesn't give a flip.
So we get different populations with wildly different solutions to the same problem.
> The human brain routinely throws away many possible interpretations of the visual data it receives from the eyes. Given the brain’s limited resources and its need to interpret visual data quickly, it can’t afford to entertain every bizarre interpretation—it simply goes for the explanation that seems most likely, based on its past experiences and built-in visual processing machinery.
That makes it sound like determining the most likely interpretation is cheap, and doesn't constitute "entertaining" every interpretation.
That would be like saying two times ten is twenty, and four times five is twenty, so division has been designed incorrectly.
So the 2D retina is just the start - our neural processing jelly is reconstructing a 3D image from it continuously. This affects how we perceive the world drastically. Lots of room to fool the algorithms. Not because the hardware (eye/retina) is faulty; because using fairly simple and efficient hardware, our incredible neural processing elicits tremendous results!