Officers already won't enforce the traffic laws we have. Ever called the "aggressive driving" hotline number to report someone? I was specifically told "if an officer doesn't witness the behaviour, they can't ticket for it" which means that report call-in number is useless.

Try calling the police and reporting that you were passed with less than 3 feet of clearance, even if it becomes law. Unless you were run over, they won't send anyone. If you were run over, they might issue a citation for "distracted driving".