Retirement funds are huge because a compulsory 10% of all wages must be invested in a retirement ("superannuation") fund, not able to be spent until retirement age. The total savings is over $3 trillion, and annual fees each year amount of ~2% of GDP (twice what Australia spends on electricity each year, and nearly as much as the military budget).
Oddly enough, it's unions and the Labor party themselves who set up this arrangement, during a neoliberal phase in the 90s.
Ostensibly, it was supposed to give workers secure retirements, but it's simply replicated the inequality of the labor market, and left the poorest people with the lowest balances (elderly women are now the most impoverished demographic in Australia, mostly due to these privatized pensions).
So it's failed to fix poverty, failed to provide secure retirements, lowered spendable wages for every working age Australian - not to mention invested in anti-worker companies and participated in privatization as discussed in the article above.
Sadly, the Labor party still defends the scheme, due to being unwilling to admit that one of their flagship projects was a mistake.