I've been preaching that for 20 years -- chronic double-digit increases are driven by easy loans.
As with a car, people wince at a $2000 radio upgrade, but an additional $30/month, sign me up!
Thus do large annual increases turn into small increases in your monthly loan.
Add in politicians favoring easy loans so all can get educations, and loan companies who don't care about risks because the government will pick up the pieces of a bubble burst, and you have the perfect storm.
One way to wrench it back down is refuse to guarantee loans to any school who increases cost beyind inflation.
Another way is to deny loan guarantees to any university with more than 50% sinecure positions (jobs directly unrelated to teaching.) Then drop it down by 1% a year until it is 20% or whatever the janitorial staff + HR is.