The applicant pool hasn't shrunk due to costs precisely /because/ of the ease of borrowing and because of ever broadening acceptance of borrowing as a part of c

The applicant pool hasn't shrunk due to costs precisely /because/ of the ease of borrowing and because of ever broadening acceptance of borrowing as a part of college life. College cost are already much higher than they should be by historical standards. I think if you examine public university tuition rates since 1990 you'll find they have far outpaced inflation. I'd estimate 3x-5x is typical, while the purchasing power of the dollar would dictate ~1.5x over that time period. The only other areas that show comparable excess are health care, energy, and the almost purely debt-driven housing market.