In what parts of the world is it impossible to view the night sky due to light pollution? Growing up far from any city, I have always been able to view the full night sky. It was just the way how things were. Of course, I knew that light pollution is a thing, and that the sky is a lot less clear if you live in a city.

It just never occurred to how bad it was before talking with people who had experienced it.

Apparently:


Inside a city, it is pretty much impossible to view anything.
It is not a lot better just outside a city, the sky is still mostly empty.
Most of Europe, parts of the US, India, and eastern Asia is so polluted with light that you can not see the Milky way.


Does anyone have a map showing the affected area? How many people have never seen our own galaxy?
Googling for 'light pollution map' gives a pretty good looking result. Those things usually are created using satellite measurments that are susceptible to scattered light (by measuring the polarity of light) in order to separate direct illumination from actual light pollution.

I also suggest you visit a city and then compare the light pollution index on this site to what you know as home, in order to get a feeling for the severity of the numbers.

I cannot answer your question about how many people have never seen our galaxy, as this is a function of travel willingness of each individual living in a city and therefore maybe even impossible to answer for our intelligence agencies.