I experimented about ten 0.2 m diameter rotors with a 5 m rope as axis. The rope transmitted only about 1/10 power, because the tension prevents rotation as shown on
And when the rope is not stretched the torque is also not well transmitted.
So a special rope which can fully rotate by using small torque, or a rigid or semi-rigid shaft is needed. If a one km long and light shaft can rotate 1 m diameter rotors without too much loss, SuperTurbine ™ could scale in any dimensions by the high number of rotors.
Scaling in numbers rather than size looks to be an option for how a sky serpent shaft can scale up.