It's the unfortunate nature of gentrification. It's also multi-layered; it's not just the middle class pushing out the lower class. The middle class is actively

It's the unfortunate nature of gentrification. It's also multi-layered; it's not just the middle class pushing out the lower class. The middle class is actively being pushed out of central hubs like San Francisco and Manhattan by the upper class (which is exactly why places like Oakland are themselves gentrifying in the first place).