Causation goes the other way: Reagan's prioritization of tax cuts over public education led to tuition increases, which lead to an increased demand for loans to pay the higher tuition.

I don't see it that way. The 80s "greed is good" mentality laid the groundwork for the fleecing, but that was not Reagan's fault other than perhaps that administration was the time when financialization of everything began. Think "junk bonds" then think "loans that can't be discharged in bankruptcy."

Reagan was the one who re-introduced tuition (at all) to the University of California system in the first place.

It doesn't--this is one of those times where the statement makes zero sense, but it was fun to bash Reagan. No, the whole story of runaway costs can be explained quite easily by the financialization of higher ed--the liberal student loan policies championed during the Clinton Administration tied to the typical greed of Wall Street bankers, enabled by the bleeding heart "everyone should go to college" drama.

Everyone got paid, except the sheep who got sheared.