I heard John Morris, the principal of Auckland Grammar, talking on the Wire about scholarship exams and related topics. He expressed the common view that less students should go to university and more should train for trades (such as plumbing).
This all has the hallmark of someone who spends his time frightening recalcitrant children with tales of how, if they don't work harder, they'll wind up as dustmen. (Kids - if anyone tells you this it isn't true - there are a wide range of jobs open to slackers ranging from musician to company director).
I disagree that there should be an ability hurdle for higher education, other than the threshold knowledge and skills needed to usefully participate in a degree course. We need to be moving a a society with more knowledge workers, not least because that is the only way we can achieve economic growth in an increasingly competitive world.