A common cycle: lots of creative, hard-working people build a thriving business district, where it is thriving because customers find it an interesting place to

A common cycle: lots of creative, hard-working people build a thriving business district, where it is thriving because customers find it an interesting place to be; then the banks want to locate there, which kills the vibe (people can walk around the banks, but density of interesting places matters), and the district stagnates as the original people sell out to uninteresting replacements. Does it not make sense to enforce some rules on who can move in next if you want to keep the place thriving? But the rules easily can go too far. For example, many a dog walker would love it if vendors could sell good, hot coffee along the dog walks or at the dog parks, but vending is forbidden nearly everywhere where it would be beneficial.