That's true, although having 19° inside when it's 30° outside is bad for several reasons. My office (in Europe) gets cooled down in summer to like 23°, and that

That's true, although having 19° inside when it's 30° outside is bad for several reasons. My office (in Europe) gets cooled down in summer to like 23°, and that's already inconvenient when wearing appropriate summer clothes. And no one is expected to wear formal clothing.