Canyon Death Falls

Recently, I've come across some trending news about people tragically falling to their deaths in canyons or national parks just trying to take pictures from way atop. Last year, it was reported that 17 people died from falling over the edge at the Grand Canyon- I understand that some of these may have been caused by something other than taking a picture, but pictures are involved in a lot of them. Since these canyons and parks are such a big tourist attraction, and many people are near the edge of these big holes daily, should there be some sort of fencing or blockage so that people can't completely get to the edge, making it safer? What else could be done so that these tragic accidents are reduced or don't happen anymore?