I'm asking out of curiosity and not trying to make a point or win any argument: Why do you draw your line there?
I wouldn't combine "free" and "partially required" though, as I don't see the need to conflate them. Where I live Masters and PhDs are free, but your required education is completed at age 15. Everything after that is completely optional, but free.
as in no tuition, but there are some administrative fees and books you need to buy, etc.
I guess I shouldn't have assumed that government would necessarily regulate college like they do high school. Some European countries are examples of that. However in those countries there are a lack of people who are qualified to work in highly educated fields and a surplus of blue collar workers. In the US the situation is reversed. There is not enough work for many liberal arts majors, but a lack of workers for blue collar jobs. Spending tax dollars educating people from jobs that lack workers to jobs that have a surplus is not good usage of the money. Furthermore, a person who is not fit for even free college (probably has a lower income) now has to pay taxes for college students (who probably will have a higher income [unless they can't find a job]) while not benefiting from it.
I'll also add that this: "However in those countries there are a lack of people who are qualified to work in highly educated fields and a surplus of blue collar workers." is absolutely not the case in the European country where I live. When you talk about the state of "those countries", what countries are you talking about and what are you basing that statement on?
Yes, I make assumptions based on what I hear and who I see. I don't have the time to make a doctorate thesis on of my assumptions. Had I spent years researching how to identify people who college would help, and people who it would not help then I would use a stronger word than "assumption". With regard to countries offering free college education there are countries such as Germany, France and Brazil that offer free college education. They also have very low rates of attendance. Image how much lower it would be if the students had to pay for it.
But to respond to your point directly, degrees such as gender studies, art history, and English literature are certainly a luxury service that can be postponed or outright skipped.