It won't happen, ever. The actual model of cities is optimized for profit, so all parts involved in building cities can take as much as money they can. Things

It won't happen, ever. The actual model of cities is optimized for profit, so all parts involved in building cities can take as much as money they can. Things will only change when the alternatives to the actual model exceed the actual model in terms of profit. Or when new players disrupt the market and divert the money flow to other model.