I dont think the problems Sydney is facing are any different to the problems many other major cities face.
I work as a consultant in engineering and construction and worked on many infrastructure and rezoning projects in Sydney before moving to New York 4 years ago. The same things are discussed in New York as they are in Sydney, as well as other cities.
However, 1 key difference is the hostility in Sydney towards developers and high rise buildings. Im not sure if this statistic is still applicable, but for population centers of 50,000 or more, Sydney ranks outside the top 500.
Sydney needs to be building up, rather than out. Inner Sydney councils, especially City of Sydney need to remove their ridiculous limitations on building heights and build enormous towers. Alternatively, we will continue to sprawl out, putting us further away from hubs, continue to build in bushfires prone land and deprive animals of habitat.
I agree with some of the comments in those articles, Australians also need to give up on the house and backyard dream, particularly in inner city suburbs. I’m aware that this means the character of those suburbs is going to change, but I dont really see any other way.
Also, 30 minute commute to work time is pie in the sky stuff for the majority. I’m not sure of many cities that have that. Maybe Tokyo, but have a look at their density statistics to see how that might be possible.