Where this becomes relevant is when you consider depixellation. True blur can't be undone, but pixellation without appropriate antialiasing filtering...
https://www.youtube.com/watch?v=acKYYwcxpGk
So if your 30x30 camera has sharp square pixels with no antialiasing filter in front of the sensor, I'll bet the brain would soon learn to "run that depixellation algorithm" and just by natural motion of the camera, learn to recognize finer detail. Of course that still means training the brain to recognize 900 electrodes, which is beyond the current state of the art (but 16x16 pixels aren't and the same principle can apply there).