It's not really useless though. Yes, in some dimensions it is terrible compared to GUI parametric CAD. But in other dimensions it is far more powerful and lets you build really complex stuff quickly and easily.
OpenSCAD is useless for almost all of the things that people actually use CAD for. There are a few minor exceptions like fasteners, gears and procedural art. Most CAD is more like a motorbike or a vacuum cleaner. Good luck with that.