It's simply less value for money these days. And government economic policy over the last 30 years has made it very clear they believe universities are more a personal empowerment vehicle, rather than a national benefit (through having a higher proportion of the population university educated).
On one hand, it's become common knowledge having a degree doesn't automatically get you a decent job, let alone a decent job, like many millennials and gen y were socialised to believe.
On the other hand, the quality of teaching has gone down, while the user-pays cost, even if it's via HECS, has gone up substantially, at the same time that people know it's going to be extremely hard to save up to buy a home these days, even with access to the bank of Mum and Dad.
Many younger people have given up on the feasibility of owning their own home till mum or dad dies, so there's less push for those people to spend money and time on increasing their earning power. That dream of earning your own home on your own effort is very much dying.
Additionally, those that are still inclined to earn enough to afford their own home, are having to judge whether the larger HECS loans, and mandatory repayments, will affect their ability to take out and pay off the larger loans now needed to buy a home.
Our university system has Americanised to a much more user-pays system, where students are expected to take on larger loans (even if it's HECS), as the government has continually withdrawn or starved funding for the sector over 30 odd years, and universities have responded by casualising its workforce, and getting rid of tenure for academics, so that the standard of teaching has fallen badly.
Not to mention the implementation of a private company-style economic model for universities, so at the same time as being starved of funding, they're being encouraged to chase international students to make up that funding, which has affected academic integrity badly, and redirected funding from the quality of their teaching and academics, to more flashy but extremely expensive capital investments like new buildings and facilities. Which are nice if the money is available, but generally it's come from badly-needed areas elsewhere within the University.
Imagine if a new funding model was proposed for our hospitals, where government reduced overall funding, but hospitals could make up the shortfall by advertising and encouraging international patients to have treatment with them. Obviously the quality and availability of treatment for domestic patients would suffer to some degree, as focus would go towards attracting international patients to help pay for those domestic patients. But it would be very easy for hospitals to lose focus on the big picture, and instead begin to see attracting international patients as the end goal, rather than a means to make treatment for available to more domestic patients.
Many classes are taught by PhD candidates or recent graduates, who are on insecure semester to semester contracts, often signed only weeks before a semester begins, and there are reports many are expected to only allocate, (or at least, will only be paid for) 10 minutes or less per student essay, and 5 minutes or less for other assessments. What sort of valid individualised feedback and recommendations for improvement can you give within that timeframe?