you can teach responsibility better I think in many ways without giving them a car to drive. As I said, we don't let our teens drive. Our 18 year old does have a license but rare use of the car. The 16 year old doesn't have a license. Our goal is to prepare them to live independently at college without us, and 25% of BYU students do not have a car. Because we won't be buying a car for our children, they're in the same boat until they can save up money for a car. So the reality is they will be getting around on a bike and public transit as freshmen. So teaching them now how to navigate the city safely without a car IS teaching them to be responsible, independent adults. In fact, we find they have much more independence—they don't ask us to borrow the car, they just take their bike/scooter and go wherever they need to go. No more do we need to drive to pick them up from after school stuff—they take care of their own schedules.
I think you can teach responsibility through a license and a car too ... I'm not disputing that. Just saying you can also teach responsibility without a license and a car and sometimes do it even better by showing them how they don't need my car and my car insurance to be able to do all they want to do in the city (we live in Provo).