Don't misunderstand me, I'm not demeaning the value of a well-rounded education. I agree that it's vital to a full life. My point is that colleges don't have a monopoly on well-rounded educations. For me at least, America's higher education system (and really, its high school system as well) depleted rather than fostered the kind of curiosity needed for life-long learning.

I'm using "young life" in the sense of "up to that point in my life". I'm now in my mid-30s and on my 3rd career (first in sales, then as an overseas ESL teacher, and now as a software developer). I've travelled to 20+ countries, lived in China and Europe, and had many wonderful experiences along the way. I'm grateful for the many careers I've had, which allow me to state with confidence that my current career is a great fit for me. But none of my experiences required that I attend the college I did and go into deep debt to do so. While (as you said) I'll never know for sure, my guess is that debt probably cut off just as many opportunities as it gave me.