Trying to restrict the non-printed ICs you'd connect to your 3D printed parts would be even dumber. There's a zillion things that can slam out bits and control a stepper motor.
you can build a 3d printer out of general-purpose electronic bits, anything they tried to ban would send ripples into countless other industries that are completely unrelated to each other or 3d printing.
By "general-purpose" I mean that there's no components that are 3d-printer specific; motor controllers and microcontrollers and voltage regulators and all the various jellybean parts. And even if there were any, they could easily be replaced with general-purpose components.
