I get it. Your perspective is completely normal. But you're talking out of fear. While it's fine to take note of it and make plans in case of worse outcomes, allowing fear to take charge of your decisions will only cause you to fall deeper into it.
Most people don't know what you think they know. Take any family and you'll almost always find gaps in their shared facts. Our presence here on Lemmy is deceiving us in what is supposed to be common sense that is often not. But at the same time, the fediverse is a good example of how many topics and interests we don't share or know of at all.
And besides, if these gun wielding maniacs are so widespread, why would running away help? You'll just meet them everywhere you go. Makes no sense to trade the danger you know with others you don't. Call it survival, but it's really waltzing away with limited resources and knowledge into the great unknown.
Less fear, more reason. Or you'll just drive yourself crazy with worry.
It might, it might not. A different study would be needed.
Hypothetically, the night lights themselves might trigger functions which need natural light in order to reach completion. This could cause a series of incomplete chemical processes which accumulate over time and eventually reach a complete breakdown.
Think of it as a program running incorrect code or a car running on the wrong type of fuel. The damage remains unseen until it becomes irreversible and the body is done for.