Look no further than supply and demand. The economy measures “demand” in dollars. The more dollars you throw at something, the greater the demand. More money for education hasn’t meant more opportunity for education... it’s meant greater cost of education. And it’s an inelastic good... so we’ll pay it.
If not for easy to get loans, the demand would much less at current prices.
The inelasticity is not a straight line.
There is also an indifference curve to consider, as well as opportunity costs.