I would still use the peep hole and ask who's there just to annoy people.

They probably wanted to add frosted window film to the glass, but then liked how the light comes into the hallway.

I think you made me discover a whole new genre there:

WHOLESOME SHITPOSTING

The 300IQ play is to paste images of the interior over the glass so that it looks like noone is inside, while you get to look through the peephole

I'd make sure to look through it every time someone knocked on the door.

You can get camera which fit these. Probably not the case here though.

I'd do that just for fun.

I have that same outside light fixture. It's shit.