I'm happy to make any reasonable bet/prediction-book entry on the subject, provided the term is short enough we'll remember.

Same here. Let us put it on prediction book and assign odds once we agree. We could even make more than one prediction.

Unfortunately for the world, but fortunately for me, the human capital model is greatly overrated. Education is not primarily about teaching concrete skills. It's a stably wasteful way to sort people according to their intelligence, conscientiousness, conformity, etc.

I think this is true.

However as cognitive science and genetics advances we may yet see say the legalisation of the use of IQ tests or other tools for employment screening. This would eliminate much of the services (and waste) associated with education. If a place like Singapore did this, it just might be a big enough economic boost that other nations might follow.

Regardless many many people who are employed in "education" are employed in primary and secondary education, very little signalling benefits comes from these two. I could easily see say the number of primary school teachers per capita dropping by more than a half in the next 30 years.

Also lectures in the English speaking world might easily be completely outsourced to just a few professors in the next decade or so. Why have 300 lecturers do the same lecture every year? Why not reuse it for a few years, perhaps even decades on basic freshman courses. Why limit oneself to questions and answers from one classroom instead of everyone doing the lectures that year as well as questions from previous years? The opportunities to use user data to optimize the lectures far more than is humanly possible even for a top performer. The differences between the signalling values of universities is not flattened in any way, so the quality of the signal is preserved, indeed if the university happens to have a one of the few top lecturers or departments that make these lectures it probably gains a big prestige boost. This might not look like it will eliminate jobs, yet it automates a significant use of a academicians use of time.

And 10 years after that, what happens if we get a Googleversity that offers a quality computer science online education? Google could easily afford to hire part-time professors or professionals or even mere supervisors to have students in key countries take the tests in person. Google could also set the standards arbitrarily high. Having a degree from Googleversity might not signal conformity but it would signal intelligence, knowledge and conscientiousness. For some jobs this will be enough. At the very least Google itself would probably seriously consider hiring any applicants from the top 1% or so. If this proves successful, other companies might follow.