Here are some other typical problems -- be careful not to come into contact with these wires, they may be energized, or abandoned.
I think that they should be removed, especially if the property values are to be elevated in your part of the world or if you want the kids to see their next birthday!
If the equipment or wires are still connected to a power source, then then must be covered, protected or removed. If they are not connected to a power source, they are not an electrical safety hazard. don
This is just silly. You are showing apples and oranges. Of course the wiring in the pictures should be denergized or made safe. However once that is done I see no hazard with leaving it or equipment in place.