Modular and rectangular boxes with magnet or some kind of attaching mechanism to sides. Standardized sizes only, which makes customers to create drawer shelf to their table.
Imagine all iPhone boxes have the same size

Questions

Carbon footprint of packaging to have not totally fitted size means boxes will be bigger than they need to be. It means less unit per volume and less unit per truck. More cardboard material per product as well.

See also

modular standardized plastic bottles