Lots of languages reify types as classes, but that's not necessary. You don't need classes to have types. Using classes also leaves entire segments of type-exp

Lots of languages reify types as classes, but that's not necessary. You don't need classes to have types. Using classes also leaves entire segments of type-expression on the table or makes them unwieldy e.g. https://en.wikipedia.org/wiki/Tagged_union https://en.wikipedia.org/wiki/Tagged_union So it's orthogonal, classes are just one possible implementation of types.