I can see no reason why the GB would want to loosen their grip on their cash cow/ cushy life. But what will they do in 20,30,50 years? Well I suspect that at some point they will claim that the promised paradise is already here but that it has come in spirtual form. That it's not going to come in earthly form just spiritual form. The old scriptures about the lion lamb etc they can just twist into being symbolic of something of course. Then all they have to do is erase the privous old light and claim that anyone who said the paradise would be earthly were going ahead of the chariot ( 1975 style).
What do you think? They will have to think up something eventually. And let's face it the GB could tell them to take a running jump off the nearest high building and the faithful would do it. But I don't believe that they would risk their cash flow like that.