That's kind of the point-Hilary got labelled a socialist despite her record. Also, many of those 75% have either children, siblings, or friends with student loan debt. And if we are going to presuppose a total lack of empathy, we might as well fold the party-it's not like the kids in cages vote.
Sorry, eliminating college debt by taxes is a losing concept for a presidential election. It plays right into us vs. them.
You can try it after the election in some form based in service and other things, but eliminating all college debt will be a bad choice at this time.