A big reason for the steep increase in prices is that as of 01 Aug 2017, all applicants are required to do a face to face ID verification with the issuing body or their agent. It is when you get agents doing the ID check for the issuing body that the additional costs come it. Unfortunately, there was no way around this. People in remote parts of Australia are really struggling getting ASIC renewals now.
Some issuing bodies had to go to Australia Post and enter into very expensive agreements for them to do the ID checks. Not only the cost of setting up the account, on top is the individual cost for the applicant having your ID checked and not all Australia Post outlets can do the ID verification.
The cheapest option is for you to go and do a face to face application with one of the issuing bodies listed on the Department's website.
Arguably the tech involved in making a passport costs a lot more, given that the ASIC is just a ****ty plastic red card.
The passport definitely has more security features but the machine to put the pretty foil strip overlapping your photo is quite an expensive bit of kit.