There are many kinds of mathematics as math is a vast field. Most of what is taught as math in HS - ie algebra, trig, geometry, and calc, are just discrete forms of theoretical topics, said topics being just a very small part of the whole. Its like being a coin collector vs learning economics, finance, and accounting. On this money continuum, calculus is akin to knowing what an annuity is.
This is why a lot of PG kids do calculus in 9th grade or sooner.
And this is why kids cannot give up at math as it is a vast field. being good at calculus does not mean you can read proofs.
