The AODocs Smartbar allows administrators to prevent users from modifying files and subfolders permissions directly from Google Drive. To do this, go to the “Settings” (1) icon in the Team or Secured Folder and click on “Library settings” (2).
Learn more here: Install the AODocs Smartbar
Accessing Team or Secured Folder settings from Drive
Under “User Permissions” (3), make sure that the “Allow permissions to be changed at a subfolder and file levels” button is not checked (4). Then, click on "Done" (5).
Not allowing permissions to be changed at the subfolder and file levels
Note that the modification can take a long time to be applied since AODocs will need to update the Google Drive permissions on each individual file of the Team Folder or Secured Folder. For a Team Folder or Secured Folder with thousands of documents, it can take several hours before the change is fully applied.