I would first caution against reducing education to the practical and the economic. Education is much more, and much more important, that just that.

Second, I would caution against the trope that invention is some exclusive province of the "genius".

That out of the way, we can look to network effects. Consider that a populace with high literacy will permit more of the kind of collaboration that has literacy as a prerequisite, while one with low literacy and a few outliers won't. The outliers are constrained in how much they can collaborate, and collaboration is essential to scientific and economic development.