Perhaps a more accurate statement would have been "thermostats are not common in countries where typical residential construction does not include accommodation

Perhaps a more accurate statement would have been "thermostats are not common in countries where typical residential construction does not include accommodations for central heat/air." Good examples: Brazil, India & China. Sure, a window unit or ceiling mounted a/c will probably have a remote control and a digital display thermostat, but that is not nearly what this is about.