Why don't myopic people see the world upside-down?
You have misinterpreted the nature of the light rays shown in the diagram in the question.  The two rays are representing light coming from the same (distant) point in the environment, that is, some small feature on an object is reflecting (or emitting) light in slightly different directions and reach the eye separated by a small amount (less than the width of the pupil).  The rays are almost, but not quite, parallel.  The two rays, coming from the same point, should be focused on the same point on the retina (as are the red rays corrected by the external lens).  The spread of the uncorrected rays in myopia or hyperopia sends them to different places of the retina, causing the image to be out of focus, not upside down.

The path of light from an entire scene can be illustrated like this:



As this diagram shows, the image is upside down for all of us, in focus or not.  That the image top is at the bottom of the retina is not especially important -- the cells doing the interpretation could have been located physically located anywhere as needed.