https://github.com/tiangolo/typer/blob/c3a4c72a4f1a18b7f16addb508862ec63411fa63/typer/params.py#L14

Why List?
Do we expect to mutate the data?
I'd expect immutable types allowed.
Maybe this should be generalized to an abstract interface such as Sequence or Iterable.
In general, any overspecialized parameters should be generalized.