It's my understanding that most monitor types (except CRT and OLED) are literally just a filter over an always-on white backlight. Is this not correct, or is the light somehow re-absorbed and turned back to energy?
Unfortunately some people will bring up these kind of topics no reasonable person is against (climate change, racism, accessibility, etc.) to support their pre-conceived notion, whether it makes sense or not. We might call this "playing the climate change card".
The weirdest part is a CS prof. ranting about -- the dark mode, display tech, etc. have exceptionally little to do with CS (which is mostly Math). Personally I'd have called the prof. on the nonsense -- google can be evil but that has little to do with their choice of colors.
Kind of; the human eye shifts to adjust for the quantity of light. The ambient lighting in the environment also matters too; both for cameras and eyes. Perception matters.
CRT was universally used in the past. And backlights are dimmed when displaying black most of the time. You can test your power usage of displays yourself if for some reason you dont believe this.
One of my old CS teachers would rant about googles evil choice of white background.