This is potentially the lump of labour fallacy. There isn't a set amount of work to be done.
If we have a mass of students learning no useful skills and divert them into useful fields, then the overall productivity of the economy will go up.
Obviously if everyone floods into a single field there's some limit: you can't productively employ 10x the plumbers without a matching increase in buildings.
But in general, better skills should lead to a better economy.
Germany has been better managing its human capital for generations with its apprenticeships, trade schools, and cheap universities. There are problems of course with switching lanes and with second tier universities, but on the whole it seems to work better.
"If we have a mass of students learning no useful skills and divert them into useful fields..."
What do we do if a significant portion of the students who already aren't learning useful skills lack the neural plasticity to become productive in other endeavors? Or in other words, how do we incorporate humans into the economy when those individuals are objectively inferior at EVERY task compared to an automated (robot, AI, etc...) alternative? Especially as we consider things like climate change and austerity, and how humans are supposedly the greatest threat to overall environmental longevity?
If we have a mass of students learning no useful skills and divert them into useful fields, then the overall productivity of the economy will go up.
Obviously if everyone floods into a single field there's some limit: you can't productively employ 10x the plumbers without a matching increase in buildings.
But in general, better skills should lead to a better economy.