None of the reprap 3D printers can fully make themselves. They all still need additional parts that can't be 3D-printed, like motors and controllers.
"Open Source Muti-Machine": The heavy, ultra-stiff mass of the cast iron dampens vibrations and forces the cutting tool to move in a perfectly straight, micron-accurate line dictated by the factory-bored cylinders.
Ask an AI about it, but conceptually it's an amazing concept. There are probably billions of "nearly micron-accurate" machines, and if you're 1000% repeatable 90° then the world is (eventually) your oyster.