to_datetime, to_timedelta, Timestamp, and Timedelta have a unit keyword that causes confusion because the term 'unit' is overloaded. The keyword refers to how we interpret integer arguments, while the result's obj.unit attribute refers to the resolution of the result. Confusion e.g. #60371.
Update: also the meaning of the keyword in date_range matches the attribute but not the to_datetime meaning.
Let's deprecate the argument and rename it to something else. Opening bid: "numeric_unit"