Any "Illegals" (those without internal passports, or those that can't use their own "papers" for a variety of reasons) become the new underclass, abused by unscrupulous employers, landlords and whoever else can stick it to them. There will be a thriving black market in services and "protection" to these individuals.
Ask yourself the question, have your activities become more or less controlled & scrutinized over the last 1,5,10 or 20 years. Before you answer that think about the use of the tax file number, 100 point check to get a mobile phone SIM card, open a bank account amongst other things. Consider how many genuine physical cash transaction you actually do in a day. Basically every cashless transaction you have ever done is sitting on a database waiting to be mined.
As an example, I recently opened a bank account. To my amazement, my profile now includes all my details of an account I had closed in 1987, and I had forgotten I ever had.