So we still need materials that don't yet exist, manufacturing capabilities that haven't been built and engineering that hasn't been tried. Sounds about exactly how sci-fi I think it is.
Why nobody else understands the ingenuity of Giant Space Carousel from Seveneves. Central mass can be at any orbit, not only 30 000 kilometers away at geostationary point. When rotation is synchronized with earth, and spokes almost touch the earth, you can just hop into the Carousel and ride to space for free.