The notion that consumers will one day be able to customise 3D designs on their computer screen and print them at home is fanciful.
Anyone who has tried to teach/learn three dimensional geometry can tell you that 3D hurts the brain.
We don't even see in 3D. The retina is 2D and we have some vague conception of 3D.
Close your eyes and consider for example the intersection of two ice cream cones.
What does this look like? Is it ever an ice cream cone? Going beyond this, there are geometric phenomena in 3D that have
no analog in 2D, which we don't naturally perceive,
The problem is that we design in 2D, our mind's eye is 2D, our experiential perspective is 2D, and our design technology is 2D.
Our perception of 3D are essentially some sort of projections of 3D Objects. It took painters centuries to even conceive of this.
(Of course, you can train your 2D mind to design 3D objects , but basically you've got to be a specialist. For these designers, why would they choose 3D printing,
it looks like a lathe tool to me but you are restricted to the material you can use. )