I think you took a bit of a joke reply... incredibly seriously
That said 78 in summer at least in my home is pretty reasonable as my house is fairly modern and has two zones.
My main culprit for messing with the thermostat has a habit of leaving their bedroom door closed all the time which causes heat to build up in their room... AC on and door closed is ineffective at cooling a sealed room so the room stays hot no matter how low the AC is set.
haha... I only cool to 78!
We do go a bit lower in the evenings during heatwaves though to help remove heat when it's cooler outside than inside... but not a big enough difference for opening windows to help.