I don't think that's the entirely the case. True it's not zero sum, but it's not free either. There is absolutely wealth transfer. For example, if he were poor, many middle class Seattle residents would have far more purchasing power in their current real estate market. Amazon have expanded rapidly and transplanted most of the cogs who are building the Bezos empire.

The many displaced multi-generational residents of Seattle and San Francisco might not refer to this phenomenon as beautiful.