In the UK, most buildings are naturally ventilated. There's no mechanical ventilation moving air around automatically, you gotta open your window if you want airflow. In the winter this generally puts people between a rock and a hard place: either you are slightly cold and sitting in a stuffy roof, or you open a window and are REALLY cold and also go broke from the energy bills :P
to which tangential, interesting information was provided but left the original question unanswered.
Are we to assume literally nobody has an AC nor is it possible for AC to even exist in those situations? Because if it helps, then maybe something productive can come out of this conversation where we can aim to improve some of these living conditions through use of AC's - which would kill 2 birds with one stone.
It seemed like a genuine question that should be actually answered. I want to assume "yes" they would help, but I'd be guessing.