As an SF Bay Area resident who walks/BARTs as much as possible, IME bicyclists are at least as big a threat to my safety as motorists, who at least have a license and insurance on the line if they screw up. I can't tell you how many times I've been hit or very nearly hit by entitled cyclists who don't think that traffic laws or common courtesy apply to them. Even worse since motorized bikes/scooters hit the streets...er, sidewalks in recent years.