It empowers the rank and file. How can you have a ruling class without someone to rule? I remember friends and family (and sadly myself) who thought we were Christ’s Secret Service when it came to MS School’s and the meetings with the CO/DO when he came through… shhhhh “I can’t talk about it”. This is one of the first few steps in setting up a totalitarian environment. Organize, then divide the people.
By entitling people to advance knowledge on a restricted basis you setup a nanny state and you give something for the lesser followers to aspire to.