Maybe they're just looking at it like it's a fair investment, and that getting something back is better than nothing? Basically, an accepted money pit, as they get the cash back from other areas like tax or whatever?
The only way to get more of that back is to hammer the students, but doing it to the ones earning 24k seems a bit harsh, especially nowadays when they're being screwed by the property ladder.
You could have examples where someone earning 24k has had their fee capped at 9k from Teesside uni, yet someone could be doing economics from one of the big three and likely to clear >50k for the majority of their career, and they also get their fee capped at 9k. That doesn't seem fair, they're both paying the same, but not getting the same back, nowhere near.
It's even less fair on some trady, who never used the system though, but who now earns good money and shells out loads of tax, but they had to lump out 30k on tools and work their nuts off for apprentice wages though, who took 10 years to get 30k, and likely who physically won't be able to work past 60.
The student system should largely fund itself I think, it's a bit unfair that those who never used it, to have to cop out for it, but they probably get it back elsewhere on average as the students may drive the economy and be the customers for the tradies.
I wonder how much of that 160bn went on failed multiple-year courses, or courses that had next to zero job prospects? I suppose that's where they could do a lot of the trimming, as in stop the problem before it becomes a problem.