Chimp climbing wires not electrocuted?
Yes, the wires are insulated. It might be due to the congested urbanization. I have been seeing the same thing even here in India, over the last 10 years. Earlier, they used to be bare wires and regularly caused injury to either people carrying long poles etc, or they got torn in cyclones and fell to the ground.

Sometimes the electric poles are very high (12 meters or more). In those I have seen bare wires at the very top, insulated ones below that, then phone and TV lines just above the pedestrian's head. The voltages of the bare wires and insulated ones are also different, but I don't remember what they are. The bare wires usually have better safeguard to prevent sagging, than the insulated ones.