City Operations

City revenues used to rely mainly on selling land.

If you're running a city, you naturally dislike demolishing dense, old residential compounds—too costly, no upside, no margin.
If you do have to demolish, and you really need that land, how would you act? You'd do everything possible to suppress the neighborhood's housing prices. Only by driving down those old property values can you buy, demolish, and resell the land profitably—profits that keep the city operations team afloat.
If the acquisition cost is already sky-high, what's left to earn?
Even in the same prime area of a core city, old neighborhoods and luxury enclaves look completely different through the lens of city operators.
From that perspective, luxury districts need their prices maintained. If values don't hold, will the wealthy still come? If they don't come, how can you sell land? So prices must stay strong.
Old neighborhoods, on the other hand, need their prices pushed down—only when they're low enough can you demolish and flip the land for a spread that covers the city operations team's costs.

When I can't sell land anymore and need to find new revenue streams, what comes to mind first? Renting. I rent out properties to generate income. Rich new residents who buy commercial housing? I make money from the land sales. Poorer new residents? I still want to earn from their rent. That's how "unified leasing" was born.

A city isn't a place to make money and send it back home.

Earn in the city, spend in the city—don't take a dime home. That's what drives consumption and keeps the city fed, not drained.