I remember visiting a client in 2014 with my MacBook running F.lux. We were working late when I heard some friendly mocking from the other side of the room: "Hah, your Mac display has such a yellow tint!" (they were PC and Windows users).

Their jaws dropped when I explained that my display's color temperature was adjusting for the time of day/night and I bet the F.lux website got some extra visits that evening.