HECS is nice, I knew a number of Aussie engineers at Microsoft who got a good education and as you said, fled the country.

Low interest loans are not the worst idea if people actually stop to ask themselves if their major will provide the enough income to pay them back. They avoid the flee the jurisdiction problem an the waste money on a useless major problem.

Its reasonably rational to pay the money to go to Stanford for CS even if you pair full freight. It's probably not economically rational to do so for sociology.

The problem of course, in the US, is that no one asked themselves if they could afford to pay back the loans given what they intended to do. Its some mass collective delusion.

The other problem, is that every time they up the amount for federal student loans, universities up their tuition to match.