Yep, telephoto lenses in general are not well suited to low light photography, so Apple just doesn't use it when the camera software determines that the quality would be worse than just digital zooming with the wide angle lens. Even the $350 telephoto lens I have for my Sony mirrorless camera stinks in low light compared to the kit and wide angle lenses.
As a general rule of thumb, you should really only use the 2x zoom when you are outdoors and the sun is out or you are indoors under bright lighting. If you are outdoors and the sun has already set or you are indoors in medium lighting or less, just stick to the wide angle lens.