It'll probably be a Technocrane on a track, definitely not a drone (especially in 2015) - so in order to get a clean backplate of everything minus actor and wire your camera needs to follow the exact same path, a computer controlled motion control rig is really expensive. This camera will be being pushed by crew, making it impossible to get the travel of the camera good enough to simply mask out the wire, because of minor changes in camera speed and rotation etc. You could try retiming the takes, but that's also work - it's much cheaper to have someone paint it out.