This seems to be a visualisation compiling different data sources, rather than true satellite images: notice how stuff outside North Korea looks exactly the same in each frame.

If you want to check out the difference for yourself, this website lets you view and compare light pollution (the rainbow colours) and VIIRS data (how much visible and infrared light a piece of land emits, green-to-red scale).

Something I noticed is that there was hardly any increase until 2023, this all happened in the last two years. If you look closely at the second pair of images, you can see lots of small towns that have now lit up, like this one.

It's still a far cry from the light pollution in South Korea (which still imports over 80% of its energy), but it's still fascinating. From what I can tell a lot of this is thanks to solar panels from China.