It's possible to make a module appear for students after they meet requirements (e.g. submit an assignment in a different module). This suggestion is to also allow modules to be hidden after requirements are met.
It's not intended as a perfect trick to hide content because if it's been available once, then we can assume it's been downloaded and saved elsewhere. However, this would allow for some potential gamification and navigation through a course. It could also allow students to make an active choice in their learning which releases new content and hides (now) unneeded options from the previous choice.