Yes, if you can get okay at printing, the friction from idea to implementation dissolves quite a bit. If you're building POCs, it doesn't matter than this gear won't work be durable or that chassis is ugly. Having it in hand for pennies means you'll actually build your idea. It's much like using packages in software. Maybe they aren't perfect fits for what you're building, but they get you close enough. You can refine later once you know the system works. The gap between idea and implementation is so dramatically reduced that it doesn't matter.