Django makes use of a whole lot of Python’s fancypants stuff. For this reason, for instance, mypy doesn’t do well on Django projects without a purpose-built plugin. But I still take your point.
pydantic also requires a mypy plugin… But it's just how it was designed. I designed typedload with mypy in mind, so it kinda works (except for some limitations in the type system that don't allow to express some things, as of now).
