In the April 1, 2017 production release, a new feature was introduced that allows students to export course content for offline viewing.
However, once an admin checks the box to "allow students to download course content and view offline," ALL courses have this enabled by default.
Each teacher has to go to their course settings to disable this feature on a course by course basis.
I believe once this feature is enabled, it should be an "opt-in" feature for courses, rather than an "opt-out" feature.
Occasionally a teacher may unpublish review content so students no longer have access to it. However, the course content export feature allows students to save a "snapshot" of the course to their machine, and view what a teacher may have unpublished.
Courses may also have copyright material that should not be passed around outside of the LMS. Exporting the course content allows people to potentially pass around a folder with much of the course content, outside of the LMS.
It's easier to explain these issues to teachers and then let them make the decision to turn the feature on. Instead, we basically spring it on them and hope they remember to turn it off if necessary.
In my opinion, this feature is needed. It just needs to be "opt in" instead of "opt-out."