On the one hand, my son (who went on to be admitted to HYPM and attend P) did drop his Ancient Greek class and took the W because it was just too much - he officially changed the status to “audit” and still took the NCL Greek Exam and reported that.
On the other hand, I think any HS student who is that advanced in math, should breeze through a community college Linear Algebra course. It’s not considered very hard even at MIT. I’m very uncomfortable with this blaming of the professor. It makes sense to me that example problems would touch on chemistry, physics, etc. as obvious applications of linear algebra.
So I guess my advice would be to drop, but also to reorient yourself in case this student isn’t quite the math whiz you expected? I agree with the rest of the responders that a math class is required both 11th and 12th grade, even if that is “a drop in rigor” to AP Stats.