Because he could just declare bankruptcy--only suckers without connections have to take out loans that Biden led the charge on--hand-in-hand with conservatives to make the debt non-dischargeable even in bankruptcy.
Conservatives only give tax breaks to the wealthy and cut actual government the poors all need, but NAFTA and the college debt bill were two of the most broadly damaging economic mobility bills passed in the last 30 years. Clinton passed NAFTA.