Even very small and cheap lidar can see cables just fine.
I work with 3d scanning lidar every day and I know this as a fact.
They have no excuse there.
In the sun, at 50mph? 50mph sets the minimum range of the scan (related to the "full stop" distance and fully loaded maneuverability), which sets the acquisition rate and angular resolution requirement to see a thin cable at that distance. I suppose maneuverability would also set the FOV requirement.
Are there any commercial drones that do it "right", with LIDAR?
Wires are somewhere between hard and not possible to see, visually. The "fix" for this might be "that kinda looks like it might be construction over there, go around".