I'm confused to why when I watch the top runs, they decide not to use any light.

There has to be some reason to why.

If you use normal screen brightness and use a flashlight or lantern, then you can only see roughly 1-2 rooms far ahead of you. With increased screen brightness and no lights equipped you can see infinitely far pretty much.

It's just that without a flashlight, you see the next room

fps boost + easier to read rooms