About “neighborhood character” and “historic preservation” as urban goals, certainly the former is a fuzzy concept, but even if the impact of neighborhood character is not quantified at present, there are ways that it could be quantified. In so far as Paris generates a lot of tourist income as a result of maintaining itself in all its Haussmannesque glory, there is an economic case to be made for these limits. However, making the case would include a lot of difficult counter-factuals. How would we estimate how many people would not have come to Paris if Paris had followed the modernization example of, say, London?
I once read somewhere that if Haussmann hadn’t rebuilt Paris in the 19th century that it would have been the largest medieval city in Europe. That would have drawn in arguably even more tourists, sort of like Venice. The rebuilding of European cities after WWII provides a lot of lessons. Rotterdam built new and modern, and is now one of Europe’s major ports. A lot of cities rebuilt their historic centers, but these centers are surrounded by modern neighborhoods that make the historic section feel surreal in its isolation. Warsaw is a particularly glaring example of this, and Frankfurt as well. Preserving the character of an entire city, as has been attempted at Paris, is one way to avoid the jarring contrast of historic center and modern surroundings, but few cities are willing to give over the whole its texture to preservation efforts that obviously frustrate new building, hence new economic development.
Historic preservation is more easily quantifiable than neighborhood character, but value judgments have to be made about what old structures to preserve and what old structures to replace. However, even if it could be proved that tourist income is generated by cities that keep their historical character intact, the motivation (for the regulations and limitations) here is probably not primarily economic. It is entirely possible that some city might choose in favor of the intrinsic value of its historical character even if they knew that this would limit growth opportunities. It probably wouldn’t be difficult to find examples of this.
