People do observe it though don't they? I do, I frequently did before it was an official rule. You don't have to whack the anchors on mid turn if you've approached the situation correctly, and no pedestrian ever, should step in front of a moving vehicle, regardless of priority because it's a poor survival strategy. Pedestrians can stop and look, drivers can stop and wait while they pass. If everyone does that all the time then no one gets run over.
If you're indicating to turn and someone still rear ends you then it's because you were being followed by an incompetent unobservant driver as interacting with pedestrians at side roads is a totally common and valid reason for someone to be stopping