Growing up in North Carolina, we had an HVAC system plus an attic fan (very loud) that didn’t cool but would pull the hot air out of the house. Nowadays, I think people just have quiet ceiling fans in most rooms. You can set the AC thermostat higher and leave a ceiling fan on and stay cool.
That just gave me a flashback to my grandfather’s house in North Louisiana. The attic fan was a noisy rattle trap. It wasn’t noticeable on the first floor but was very, very loud on the 2nd floor. No AC either.
The up stairs bathroom vent fan gives a significant change of heat elimination, but are not made for that use.
But the up stairs bathroom vent fans show what is needed.