It is a function of population density. If the density is low, you need a car. Alternatives don't work. If the density is high, cars don't work. In between th

It is a function of population density. If the density is low, you need a car. Alternatives don't work. If the density is high, cars don't work. In between there is a bit of a choice, streets that are friendly to pedestrians and bikes encourage people to walk, cycle and take public transport. Streets only designed encourage traffic jams. Cars create traffic jams in a way that doesn't seem to happen with other modes of traffic. In a medium density environment, if you like traffic jams, go for cars. There is a also a bit of a question how much children can move around freely. In areas designed for cars, children tend to have very limited freedom. Their parents have to move them around until they get a driving license.