Humans are perfectly capable of driving on racing simulators using a flat screen though, where binocular vision makes no difference.

And Tesla cars have more than one camera on them. The front-facing camera is actually an array of 3 cameras (the two farthest ones are at about human eyes distance), but they're also equipped with forward and rearward looking side cameras, and back cameras.

I think Tesla underestimated how hard vision-only FSD is, but having a single camera (they don't) is not the reason.