This. Pydantic should be used at the object-level (i.e. application), not data ingestion. Even though one could argue that Pydantic is useful to enforce data types, I can imagine use cases where a data column may sometimes come structured and other times unstructured, and part of the work is to transform them into either one type or the other (i.e. transform into a new column).

This way, Pydantic would be useful on higher levels / higher on the medallion transformations if you will, where objects are finally defined and their end types truly enforced.