I believe this "myth" comes from some office buildings where the lights are changed by union help. They probably need to have them on for at least 14 or 16 hours a day anyway so the savings in electricity is not as much.
I have seen those same buildings use electric heaters in the AC ducts to control the temperature in each area. The AC ran full blast 24/7 and the heaters reheated the air to a more comfortable temperature. 1950s thinking. I doubt that very many such buildings still do that. Likewise for leaving the lights on 24/7.
As my father often said, "Turn the lights off".
Make it fit.
You can't win and there is a penalty for trying!