if you look at what i said, im not bashing talented 3d work, im just saying its easier to get there than it would be comparatively to 2D, because alot of the skills people start out with in life can be applied.
ive done 3D and i know that to make GOOD lighting, you need to know what you're doing, but i find modeling in 3D to be much easier than drawing something similarly good.

When i draw i have a semi-complete idea in my head, and it adapts as i go, same goes for when ive worked in 3D, i just adaptively worked, and i didn't have to stress about things like the angle and perspective i was working at, cause those were readily changeable, i didn't even have to worry about getting my shading to match my forms, cause the computer DOES make a good approximation of real world lighting.

i dont know why you say that you need a vision of the 3d object in your head for 3d but not for 2d, if you ever actually draw anything from a view apart from a cardinal angle, you need an EXTREMELY good sense of the objects shape, or else what your thinking will be completely different from what your drawing, you even need to account for foreshortening and light direction IN YOUR HEAD.

when your working 2D an ugly angle and perspective will stick, no matter how good your forms may be, simply because 2D isnt 3D. and yes you might argue its a gross simplification of lighting, but really, doing lighting in 2D is the same thing artistically, and your relying on your vision much more than you would be adjusting lights/renderers in 3D, once you commit in 2D its a done deal for the most part, without completely redoing anything nothing can be changed apart from little things.