They taught me about matrices and vectors and common matrix/vector operatoins in pre-calculus and even earlier in a shitty public school.

Calculus needs to happen in high school so that people are more prepared to take it again in college. For me, calculus 2 was the hardest class in college. This is coming from someone who went to a math grad school.

Some people need to study way more for calculus than for any other class in high school or college.