it's possible the necessary inventions would have happened earlier without the patent problem, but the minimug era of reprap was not simply reproducing existing fdm machines; they were having to figure out a lot of things nobody had figured out before, like parts cooling fans, pla to use lower temperatures and avoid the need for a heated build chamber, threaded rod truss gantries, avr g-code interpreters, and eventually auto bed leveling, pla pinch extrusion, etc. there are things people could have told them, but if they'd done everything in the safe conventional way they would have ended up with a two thousand dollar machine