[animefan]

Generally "efficient" means maximizing social utility, which in practice for economists means GDP [0].

I agree that there are benefits to an educated population (in spite of disagreeing with the progressive bias in university education). But you are wrong that "efficiency" is meaningless or means "making us all incrementally more efficient at doing whatever it is precisely that we're already doing". Efficiency means increasing the size of the "pie" so that however we choose to divide it up, there is more pie to go around. We could divide the GDP from the year 1800 as evenly as we liked and not reach the standard of living of 2015.

[0] and no, the broken windows fallacy does not apply here, no one is trying to literally maximize GDP, but GDP represents the kind of thing that economists care about.