> What is obsession with the light

It is historic, electric lighting was the first major application for electricity in households.

" Electric lighting is highly desirable. The light is much brighter than oil or gas lamps, and there is no soot. Although early electricity was very expensive compared to the 21st century, it was far cheaper and more convenient than oil or gas lighting. Electric lighting was so much safer than oil or gas that some companies were able to pay for the electricity with the insurance savings. "

https://en.wikipedia.org/wiki/Electrification#Benefits_of_el...