I saw a poll they did where they asked parents if they thought public schools are good, and most people say they're bad. But when they followed up and asked specifically about the public schools their children go to, they have high opinions of them.
Same shit with crime. People think crime is off the charts everywhere else, but their community is fine.
I'm basically just making a guess, but given how efficient small heat pumps are, it seems like gains you'd get from scaling them up would be lost in the process of moving the cooled refrigerant/air farther.
In my area 2 recently constructed, supposedly energy efficient, apartment buildings went with individual heat pumps for each apartment instead of central heating/cooling. There might be some other reasons for it, though.