I was good in math if I studied, but even with that, I left with 70% in the advanced course with a ridiculous amount of studying. It was above the class average, but no where near the kids who were smart at it (and who did it with much less effort). However, I didn't learn the kind of math I needed for economics and policy (i.e., the areas I ultimately went into), the course was more geared to STEM.
I agree, there are way more gradients than academically and vocationally minded. Even within math, you have at least 6-12 routes, i.e., STEM, medical workers (nurses, pharma-doctors, etc), business and finance, economics and policy, architecture, etc.
However, the education system needs a revamp. We need to move towards small (5-7 kid) class sizes, expose children to specialized teachers at an earlier age (like 5-6 instead of age 12-13), more aggressive filtering and batching (e.g., find the genius kids early, make sure kids are in the "right" environment for each subject type based on aptitude, interests and goals), and build good study and health habits very early on.