How do you know what loan you can afford before you have any income? How do you expect a 17 year old who's never lived on their own and only financial experience is maybe a part time job to be able to comprehend money on the scale of 10s of thousands of dollars?

Sure you can try to be smart and look at the BLS data to get an estimate of your income after college, but a ton of minutae gets lost when doing so, such as what you'll make early on in that position vs after 20 years in that position, regional pay differences, etc. that also assumes you'll graduate and get a job like you researched in your field but maybe you picked a field that's about to collapse for reasons outside of your control, maybe the field you picked is already saturated with talent, or is experiencing some other significant shift.

I worked with one person who had gone to university to be a biologist just to graduate right after a significant number of university research positions were closed and laid off, leaving him fighting with folks who have 20+ years of experience for a handful of job openings

Student loans are the one type of loan you can't simply perform a debt to income calculation to determine if you can afford the loan. There's a million and one things that can happen between when you accept the loan and when you start paying on it that can greatly impact the affordability. The risk of course grows with the cost of education, but so does the potential reward.