And with plastic melting (FDM) 3D printers - they really don't have anything novel, just a bunch of steppers + heating element, all controlled with a cheap 8 bi

And with plastic melting (FDM) 3D printers - they really don't have anything novel, just a bunch of steppers + heating element, all controlled with a cheap 8 bit microcontroller. Yet AFAIK due to some patent being held by Stratasis that made only professional level horrendously expensive and proprietary 3D printers that never got any wide adoption, the 3D printing revolution was held a decade+ until the damned patent finally expired. And the rest is history.