(Some sort of way to store permission references with relatives paths in a file, but which most probably wouldn't work with files being exchanged cross-platform, and other than that mainly being able to get automatic access to 'related' files, i.e. same file name, but a differing extension – that solves some sidecar files, like video subtitles, or certain kinds of georeferenced images, but large capability gaps still remain – even the video subtitle example stops working if the file name is no longer 100 % the same, like if you have multiple subtitle files for differing languages, where VLC for example supports prefix-matching the video file name with the subtitle files.)
And while your idea does have its merits, I fear that pretty soon you still hit a point where you can't sensibly and succinctly display those more complex types of permissions in the UI.