It was forward looking, so survivorship bias doesn't fit. But it may be fair to say that it was unrealistic to think that it was tenable. Reality can certainly give theory a good beating.

> And money doesn't just rain from the sky

If you are going to college to do anything but create capital, the money must be raining from the sky. It would be pretty hard to justify otherwise given that there has been no economic benefit from it. As before, the promise of higher incomes never materialized (obviously, they were promised on the idea of people using college to create capital) — incomes have held stagnant.