They literally haven’t changed the temp they serve it at:

https://en.wikipedia.org/wiki/Liebeck_v._McDonald's_Restaurants#Coffee_temperature

then let it fall into a cold container that soaks up much of the heat, and maybe even pour it into another cold container afterwards, which is where you drink it from.

If you’re serious about making coffee then you’re preheating everything that the coffee will contact.

That might be more to do with your social circles. There was a shit ton of teenage drinking happening when I was in high-school.