The whole concept is unfixable. Once the fibre comes out, it's not going to go back in. It's that deadly combination of fragile and cheap. Just unpack a new drone and off you go. Don't spend a week (and 10 casualties going into the grey zone to collect it) winding it back up only to find it's broken in the middle.

No, it's a one-time use kamikaze device. The fiber intentionally, continuously, invisibly drifts to the ground.

The drone contains explosives. You really do not want it to come back to you in one piece.

Cables drones would (and likely do) make better relays than as attack drones. A relay drone flies out to the horizon and relays the LoS signals to an attack drone flying over the horizon from the perspective of the base station.

The relay then gets to spend far more of its power budget on the relay-drone segment and has a very low power relay-base segment. Relay drones also perform surveillance while they're on station. Better bandwidth to the base station from a "wired" connection means a higher fidelity feed or potentially additional cameras to cover a wider area.

The consequence, problem is ending up with long strands of basically invisible fibers everywhere. But that is a problem to solve later. After the defeat of Russia.