For a camera exposing onto Kodak 5254, probably the fastest available in 1975, blazing ISO 100 film stock. Yeah it’s dim for that. To your eyes as I understand it’s pretty well lit.
Arguably a youtube rending of a compressed digital source viewed on a computer screen falls short of a 1970s full cinema via film live viweing.
Technically it was pushing well past the envelope for the day: https://neiloseman.com/barry-lyndon-the-full-story-of-the-fa...