Being pluralistic doesn't mean tolerating cars in the city. Where possible, pluralism would ban them. Here's why. In philosophy (if not, yet, in urban planning) pluralism is distinctly different from relativism. Relativism says I have my truth and you have your truth, and from where we each stand we're both right. Employing relativism in city planning would lead to absolute chaos: pilots choosing to land their aeroplanes in school yards; owner-builders whacking up houses in the middle of roads—a complete free-for-all leading to out and out war before lunch time. What we want in built environment planning is pluralism. Pluralism does not say that all views are equal, or even valid. At the metatheoretical level, a whole category of views are automatically annulled, those being views that claim to be the one truth. Once you're in the headspace of pluralism, you take pluralism to be the meta-theory and things like Jihadism to be ground-level ideas—in that case dismissible because its monistic. Pluralism also dismisses views that are unreasonable. Is it reasonable to say the built environment should continue to be designed around cars? Given the world's energy needs and problems with chronic illness, of course not. Is it reasonable to go on accommodating cars in cities that are now too sprawling to be car-free? Yes, that's a reasonable view.
Even among reasonable views, though, there are views with stronger and weaker logic, and it is pluralism's inclination to rank them. If an argument can be made that Transit Oriented Development (TOD) is a better way forward for sprawling car cities than simply building more densely with basement garaging, pluralism allows for planning bias. If an argument can be made that Bicycle Oriented Development (BOD) could even be better than TOD, than the greatest bias of all among planners would be toward bikes. If an argument could be made that cars on the ground plane were stopping the bike city from coming into being, when the bike city would bring the most good, then motoring would be treated as we treat Jihadism. All those sentences started with the word "if" because my aim here isn't to say that cars should be banned from all cities or that all cities should be given mostly to bikes. I'm just illustrating some of the logical processes that are attendant within pluralism, that we forget in our rush to adopt its novel aspects. Getting into the heads of others (or Others, capital-O) is the defining thing about pluralism. It's why it's different to be alive now than it was in the fifties. It's why we need to understand the challenges faced by the person stuck with a house on a hilltop who has no other option than leaving home in their car before we criticise them for wanting to drive into the city. It's why I like hearing from visually impaired people regarding the hazard, to them, of bikes in the city. The logic of pluralism, though, is radically different from that of relativism. Relativism says Jihadism is right, for the Jihadist, even though Jihadism adds relativism to its huge death list. You go down a rabbit hole, real quick. Pluralism in arts theory is another matter. If the choice were between a world where every creative work was somewhat the same or radically different, the world with difference (we expect) would be more representative of us and fun. In art theory there is no real need to make a distinction between pluralism and relativism and given most urban planners receive training in architectural schools, where scholarship takes its cues from art history and theory, we have a situation where those who decide what is built don't know that pluralism and relativism are not the same. The result? Urban planners dictating the construction of car parking stations on the basis that some people might want to drive cars and it would be un-pluralistic to stop them.