Mr. McGrath, student loans are mostly paid by the taxpayer already.
They are written off after thirty years.

Guardian 3h ago,
"Student loan debt in the UK has risen to more than £100bn for the first time, underlining the rising costs young people face in order to get a university education."

""As fees increase this number will only go up, as more and more money is lent out each year. There is some cause for concern here, mainly for the government, as it is now widely accepted that the majority of graduates will never pay off their whole student loan debt before it is wiped off 30 years after their graduation.""

"Burnside predicted that over the longer term, student loan debt was likely to double to £200bn in six years."

"Loan repayments in the UK are dependent on graduates' income once they start working, with those earning more than £21,000 a year required to pay. Graduates earning at that level are obliged to repay 9% of what they earn above £21,000. However, after 30 years, any outstanding student debt is written off."
(Sorry. Dave's and my previous posts out of date!)

"Our student finance system removes upfront financial barriers for anyone hoping to study, and students only pay back what they can afford based on their income. There are now record numbers of young people, including those from disadvantaged backgrounds, benefiting from higher education."
https://www.theguardian.com/money/2017/jun/15/uk-student-loan-debt-soars-to-more-than-100bn