That's actually how we visualize 3D with our 2D retinas and monitors. It is a perspective projection: objects that are far away (in 3D) appear smaller (in 2D).

That's actually how we visualize 3D with our 2D retinas and monitors. It is a perspective projection: objects that are far away (in 3D) appear smaller (in 2D). Making a perspective projection from 4D to 3D, and then from 3D to 2D for display is simple mathematically, and it could be done in wireframe mode instead of what is currently, I think, a simple orthographic projection. In fact, it is very possible that the author tried it but didn't like it enough to include it.