Certainly we're free to act in an individualist way, but we need to take into account the social and environmental factors, and especially the latter gets more and more stringent.
If you use a car, you're polluting my lungs and the environment. If in 50 years from now, cars will be emission free, well, great, but the situation now is what it is.
If you use a car, you're contributing to putting at risk bike users and children.
If you use a car, you are traffic.
So again, you're certainly free to do whatever you want, but we should extend the analogy with books, to a world where, say, paper is limited, and books wrappings are thrown into my private garden.
I understand the blogger concern, even if it's difficult to agree with such statements. It could be translated less angrily that it's disappointing that SF people are failing to take into account communal factors when thinking transportation, under the assumption (that he makes) that people in SF is supposed to be culturally more aware of them.