Risk sharing between students and public tertiary institutions will essentially make institutions liable for some payments that graduates are unable to make in a timely manner. This incentivizes the school to keep tuition down and the quality of education up, as to have well-qualified graduates who are likely to get jobs and make payments. Further, this system would keep students honest through the use of benchmarks to determine eligibility. If a student doesn't meet eligibility, they can no longer benefit from this program.
Risk sharing creates an incentive for institutions to reconsider their admissions policy, which would favor higher-income students who can afford to pay more tuition. This is inequitable and puts low income students at a disadvantage.
[P1] Student loans are a given when it comes to public tertiary education. [P2] If the institutions are partially liable for non-repayment, they are incentivized to provide a higher quality of education.
Rejecting the premises
[Rejecting P1] Students with the means to pay for college in full can circumvent any student-loan policy with ease.