My tuition was around $15,000 per year. You are more than welcome to investigate where that disappears to (presumably not all to staff salary), but requiring me to pay $100,000 upfront would have killed my career before it ever started-- unless of course you convince employers that a degree isn't needed.
$15k for tuition alone (not counting books/materials/food, room and board) obviously makes that impossible.
It isn’t going into teaching staff. It goes into administrators salaries, bloated programs/overhead in sports, recruiting program costs, fees for housing, fees for food, and ever larger endowments that somehow never trickle down - among other things.
For what is being taught 99% of the time, the economies of scale make $2500/yr for tuition perfectly doable in a typical undergrad environment - if anyone wanted to. And it is done all the time in Europe, for instance.
If you’re taking out a loan to cover all your living costs + tuition than obviously that is going to be more expensive than tuition alone. In Europe where school tuition is covered, there are also separate programs to cover student living costs - which are also not super high generally. My ex-gf got her physics degree from a well known university in Spain, and they paid her $500 per month or week (forget) to cover living costs at the time I believe which was more than enough.
She wasn’t eating imported caviar, but students in general have always been able to get by (and have fun/a social life) without big expenses.
Every professor or co-professor I know gets paid peanuts, gets poor support, and gets waaaay too many students. These folks are at Yale, Princeton, etc. It’s a scam and the money disappears into the machine with little accountability and a ton of hand waving.