It was always a dubious claim that lack of parking led to downtown's downfall. If everyone needed massive amounts of parking to make downtown Detroit viable, then how did it become a dense center in the first place? And why are all of the most vibrant urban centers so short on parking?
The truth is that space is too valuable to vibrant urban centers to dedicate so much space to unproductive uses like parking. It is simple economics. To build a vibrant urban center you need ways to move people in, out, and around, that doesn't require half of the space to be unproductive dead spaces to store cars.
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