None of those are links in a chain of private markets. They are their own government monopoly markets.

If the government is going to become the defacto credit rating agency, they might as well be the defacto lender. Obviously loan rejections and low scores will be unpopular and an easy lever to push on for more votes, so just ditch the credit ratings all together and have a government lender that lends taxpayer money for all loans at a flat-rate.

Which basically has happened already - student loans - and we all know what a rosey picture that is.