Many readers are all too aware of road traffic jams around Sydney airport. It is especially bad at peak times such as the start and end of school holidays. We understand that the airport can and does call on the NSW government to amplify roads around the airport. Roads ministers are happy to oblige as far as realistically possible but generally succeed only in attracting still more traffic to the area.
A better approach would be to develop public transport services. Several strategies are needed ...
There is still a heavy gate surcharge on rail fares to airport stations. This is no longer required by the original contract - learn more. It could and should be lifted immediately.
Sydney has a useful network of (usually red) MetroBus services. Unfortunately, the network does not include Sydney Airport.
Part of the reason for this is anti-competition clauses in the airport railway's contract. Also, the airport likes cars and the parking fees they pay but is not so keen on buses. The clauses should be removed and the network gap filled with Metrobus airport services, providing frequent limited-stops buses in several directions reaching as far as Macquarie Centre and Bankstown etc. Appropriate bus priority should be provided at the airport.
Sydney Airport is close enough to be included in the city's Metro network. The foundling Metro rail service should be augmented by several new lines servicing inner areas and improving connections to the airport. The stations should be about 1km apart, much closer than presently planned.
All of the above should happen instead of continual road expansion. New road space is quickly saturated by new traffic; congestion won't be solved without public transport.
For an interesting discussion of airport transport, see http://humantransit.org/2016/03/keys-to-great-airport-transit.html.