Components are pretty easily done via pick-and-place, which was just demonstrated on video:
https://www.youtube.com/watch?v=MGZ0qpPN1uk
once one can make traces in 3D as part of a case/shell/frame/structure things get _very_ interesting --- consider that one electronics designer actually worked up a 3D CAD system:
just for making 3D printed enclosures:
>My primary use case for 3D CAD is designing 3D-printed enclosures for my electronics projects.
So, imagine what folks like that will make when they are able to 3D print a full circuit board as part of a structure, with components place/oriented in it in novel ways (heat dissipation? LEDs to indicate status?)....
Though, I generally like the idea of circuit traces embedded directly in mechanical design of a product, I suppose this would make devices completely and utterly non-repairable. Not that there's something new in this, but imagine, debugging a 3d volumetric circuit, where chips and discrete components baked solid into medium? And I also wonder, where such super high level of integration would be necessary, other than medical/wearable/implantable devices...
The smaller you can make things or more integral the more interesting you can do things - vape carts are a good example where it might actually reduce the total ewaste if the chip and the body were integral (though clearly would still create it)
Design the "board" as a central component w/ one or more snap-on ocovers?