This idea has been developed and deployed to Canvas
Some instructors require the Files area to be visible in their course. If a file is uploaded to the Files area a notification is sent to students who have chosen this setting. Even if the file is set to 'only available to students with a link' a notification with a link is sent.This notification constitutes a 'link' and the file is then visible to the student even if no content in the course links to the file.
This is a problem for us where a term paper is uploaded for an assignment, but there are students with different starting times created through assignment overrides. Even if we schedule the release of the file, students with a later start time (and therefore no link in the course) can get access to the file.
It would be preferable if new file notifications that have access restrictions are only sent when the student has access to the file.