True! You are right!
https://www.resilience.org/stories/2013-03-06/the-mechanical-transmission-of-power-3-endless-rope-drives/ : “As we will see, this makes rope transmission more efficient than any other alternative up to a distance of a few kilometres.” and "Transmitting this energy to Earth is most advantageously done by mechanical power transmission, says researcher Dave Santos from KiteLab Group in an interview:
“Electric cables would be too heavy. With kites, power-to-mass-plus-aerodrag is critical, and the mechanical case wins by a large factor. Wire rope is not quite so amazing as our new materials, but good enough for a critical advantage over electrical. The main challenge is to learn how to drive ropes at speeds of hundreds-of-miles-an-hour.”"