I agree with you that education's value is in its signalling (I'm excited for you to read The Case Against Education). But signalling isn't 100% of the value of the education--maybe more like... 70%? hard to quantify--and I believe that's where there's room for ideas about what that education should consist of. After all, if we're gonna make them jump hoops for four years, they ought to be doing something socially useful during that time. I like Pinker's articulation. It's concrete, for one (get out of here with that "the purpose of college is to find yourself." I don't like the federal government subsidizing something so vague). I agree it ought to impart humanism and intellectualism.
Okay but let's break it down further: I can go to community college for about $100 per credit per quarter around here. If I were to go full 180 credits, I'm looking at $18k for an education. Fuckin' shitballs crazy for community college - when I got my undergrad the rack rate was about $110 for a PAC-10 university. But it's a fair shake less than the rack rate of $270k Harvard gets if you aren't one of their financial aid cases (in fairness to Harvard, they give out a lot of financial aid). So. What's the value of $270k of Harvard vs. $18k of South Seattle Community College? I would argue it's 100% signaling. Yeah - you're going to have an overall better education from Harvard. But my grandparents got within a year of graduating Harvard and Radcliffe (and then had my uncle, who got into Harvard and committed suicide the first semester there, thereby blackballing my family from Harvard forever) and a Harvard education without a Harvard sheepskin was good enough to make my grandfather a union shop foreman. A Radcliffe education without a Radcliffe sheepskin was enough to make my grandmother a librarian (not head librarian) at a state school. So somewhere between three years and three and a half years at Harvard - even back before the GI bill, when going to college wasn't all that common - was worth about as much as going to college anywhere. My grandfather's brother finished Harvard. He helped invent LORAN and had a long and illustrious career at EG&G. My grandfather's uncle finished Harvard. He helped invent heart transplants. My grandfather's niece finished Harvard. She's an executive at Morgan Stanley if I recall correctly. But because my grandfather was a semester shy, he learned to operate a lathe.
I left 30% room for non-signaling value because, ya know, literacy and numeracy. But yea, it's sheepskins, baby. Consider. No one would stop me from walking into a classroom at Cornell or Princeton and sitting in a classroom and listening to the professor everyday, all semester. Hell, they'd probably be flattered. Furthermore, a world class education exists a few clicks (or a library pass) away. But try slapping that on your resume. I spent five years as a college dropout variously partying, traveling, working, and volunteering in all manner of places (alpaca ranch, elementary school, summer camp, to name a few). Made a lot of friends. Had a lot of fun. Had the formative experience living by my own decisions chasing my fancy, scraping my knee, and gaining some perspective. An employer sees a five year gap in employment. It was only because I had an (ongoing) degree at Tailgate State that Morgan Stanley offered me an internship. Non-conformism, no matter how ennobling, just does not look good.