That’s not a straight line, although it is possible to follow without changing direction😊

I did not in any way mean to suggest sensitivity is not a factor, only to suggest that light sensitivity may be more of a spectrum and that there are persons living in a darker world than others. So, it may not be a person on the top of the bell curve that need more light, but someone on the other end of the spectrum entirely.

Since the top comment in this thread was about needing more light in an already bright room i meamt to say that there might be reasons why people around us prefer 1 or 100000 lumen…

Apparently all eyes are not created equal in ability to transfer light to the retina. Some has narrower or wider fields of vision as well. So, where your eyes may be well adapted to low light levels, others may not be. In a world with no artificial shadows and the sun high on the sky for most of the year, being able to filter out sun light might have been a pro, while now needing lots of artificial lights to see straight.

Just renove the ball and it becomes obvious