"Also, most college majors do not require differential equations or organic chemistry. "
Each major has certain intermediate and advanced courses that 1/2 of students can’t master even in the major they pursue. So there are some courses in CS, Physics, Psychology , Sociology that are not differential equations or organic chemistry but require similar caliber
Regarding European Univ vs American Colleges, some country’s colleges won’t let you change major easily nor let you take electives from other departments. That also reflects in the cost.
I would if say one can afford $12K for their toddlers in daycare, then shouldn’t complain their in state tuition is $15K. Those who “truly” can’t afford $15K in-state tuition, I think the current financial aid systems can help them out.
It is hard to set a number that is affordable to all or most, unless it is close to free but it makes no sense. At least for those who get less than 2.5 or 2.0 GPA, why pay them to party. If one can’t get 2.0, maybe that college is not meant for you. Go get a job, when you are ready, apply as adult students.