Sydney (as in "City of...", not just "Airport") is in danger of becoming what some the greenies seem to want the whole world to be... What it started out as: a tent encampment for a bunch of people who really don't want to be there. Everything's falling apart or inadequate to service the number of people who want to use it.
As for the airport... It's almost as if someone has said: "Let's try to do everything the wrong way around... you know, exactly the opposite to the way it's done everywhere else and been proven to work well... and see if we can make it work."
The curfew at Sydney is the Aviation equivalent of the old road rule that said a man had to walk in front of every motor vehicle waving a red flag. It's as if that rule was still in place.
It was designed to protect people from the noise of first generation jets. The noise made by modern high bypass engines is a fraction of what the old jets made, and the effect today's aircraft have on the surrounding areas, particularly if arriving on 34, is miniscule. It simply HAS to go, (but I'm not holding my breath).