A young person with no income but good academics and a plan to study something with good employment prospects would still be a good candidate for at least some amount of credit.
Another side effect would be that with a drop in people going to college, employers would be forced to drop the "college degree required" from the vast number of jobs that really do not require a college education of any kind.
That's not what would happen. What would happen is that rich kids would get to go to college no matter how prepared they were or what major they chose, and poor kids who prepared well and chose useful majors would not be able to afford it.
Look at any first-world country that has kept college education affordable and you will see that they are essentially propping it up as a social welfare program, capping tuition, and giving universities tons of money. No country has kept college education affordable through any other method.
That's also the way it used to work at state universities in the United States, and that's why kids were able to work summer jobs to cover tuition.
If you take away the loans without also significantly increasing funding for higher education, college will not become affordable again.
Student loans existed before government guarantees, and all non-direct loans issued now lack government guarantees, so the evidence is that this claim is false.
If they give an 18 year old $30k for a car purchase they come take the car when you don't pay and get most of their money back. There's no way to seize a diploma to recover their money.
Student loans can be discharged in bankruptcy, but it is harder than other unsecured debt.
The interest rate? 12.79%
If you remove the government backing you might as well just not bother having student loans at all.