I saw this news pass by yesterday and took note. To set the stage, I am a rope rescue technician with many years of experience on a fire department. I tried to figure out how I would get these people off of their rope system safely (for me and them). There are a few options, but the first two that came to my mind were.
1. Use a rope haul system and pull them up. (Safe for me, not as safe for them)
2. Pick-off - This is a method used for when window washers are stuck (or other people hanging from a rope). This would require a rescuer descending down their own rope system and transferring the protestor to their system. (more risk for the protestor than rescuer)
I stopped trying to find options at this point because all options had un-need risk to the protestor and rescue workers. Every time I have gone over the edge to help someone they have been a) unresponsive or b) happy to see me. I'm not sure how these protestors would respond to a rescuer trying to stop them. Would they fight? There are more what-ifs to this situation. These people are clearly experienced climbers and comfortable where they are. To them the risk is currently low. Start adding variables to the equation and it could get ugly.
At the end of the day, these people will get hungry and will come up/down for food. Let mother nature convince them to get down.
3. Use a fine mist of water to get them wet and become uncomfortable. Let them come to you.
Safety is definitely what the rescuers are thinking about right now.