[Dengar]

Sibyl, despite its flaws, is kind of a cornerstone for the P-P world's society. Removing it will break more than it mends.

For the ending, either the above happens, or the Sibyl system remains but something will be different. For example, Sibyl itself could change to be more progressive, like try to find a way to combat the lethal apathy that's plaguing the nation, maybe introduce a little freedom here and there (bit by bit, can't do it all at once or society will break), while retaining the psycho-pass scanner. Say what you will, the psycho-pass is a very nifty thing.

For another option, the Sibyl system could remain without anything changing at all. That would be of course a downer ending, quite opposite the downer ending I mention at the top of this post.