For example, a better question would be "Why don't we eliminate <high-school-biology> and teach finance instead?"
I think there's too much algebra in secondary school (and not enough of it in college).
Few people are gonna miss matrix multiplication after school.
I strongly support adding personal finance and logic (philosophy of arguement) courses to the core curriculum.
Alternatively, I would drop things to 3 years of English to add a year of Home Economics that covered basic cooking, practical nutrition, taxes, personal finances including insurance, and saving for retirement. All I can recall from mine was a few weeks we learned how to fill out a check and sew a pillow.
I don't have a good argument against, but this makes me sad to read. learning all the names for different shapes was the first (and last, until I got to college) time that I found math interesting.
We could have at least spent some of that time learning about finance.
I'm also pretty sure a lot of my courses, could have been truncated to allow extra time for another class - I don't see why it has to be so binary.
We have this debate about math and reading. Finance? Good luck.
I found it much more interesting to study things with practical implications, and I also think embedding financial literacy into maths might be a good idea.
I'll add that I did of course eventually find uses for some of the things I was taught in maths class: path finding algorithms for a game AI, neural networks, genetic algorithms, all sorts. But in class, I didn't know any of these uses.