I consider the one page principle to be a great rule for crafting any kind of content. An entire system should be understandable in a single viewing area, which can expand into any number of viewing areas to provide more nuance.
Many parts of computer systems are not very opinionated but files very much are. You can choose to put as much or as little into them as you choose. Files should be understandable in a single viewing area, either by only having enough content to fit in a single viewing area, or by being summarized in some way that can fit into a single viewing area.