As much as I agree with you on the importance of good public transport, I am hopeful that the "car culture" will evolve into an alternative to the existing public transport systems; Once we have self-driving cars running on clean energy operating in an Uber like sharing economy model, there will be no need for car ownership and the cost of a ride will be low enough for the majority of people to afford. I understand that this is more difficult to achieve in reality than in ideas but I am hopeful. About health related issues, we will still have to look for other ways to make a healthier society.