But children do manage to ride bikes safely all over the world every day without any formal training. On the other hand, adults who have had training and are licensed to drive still manage to cause accidents.
Not in city centers on busy multilane inrersections, at least not in my country. We arent talking about riding a bike in a park or in the suburbs. And kids cause a lot of traffic accidents as well, regardless of their mode of transportation... Nothing will eliminate accidents. Training and systems can minimize it though.