[dragonwriter]

> it is ridiculous that we don't have a single commonly used standardized-exam that evaluates proficiency and expertise in the core curriculum.

We, for decades until this year, had a single commonly used set, of which different institutions mandated (or accepted as one of several alternatives) different subsets, the SAT Subject Tests (formerly SAT II, formerly Acheivement Tests.) Like the SAT itself, they've bee questioned for a while, and the COVID-19 pandemic on top of that led to their widespread abandonment and, as of this year, discontinuation.