I can’t believe that nobody has mentioned the Prusa FDM 3D printers are, and have always been designed in SCAD[0].
This alone has been instrumental in allowing community improvements, it’s the last “true” reprap, they run a farm of 300+ machines and iterate parts somewhat frequently.
Pretty amazing that there is one molded part on the entire machine, the spool holder.[2]
There was also some “archeology”[1] on the traditional CAD dead-ends from a specific extruder design that I found facintating.