RFC: unexplicit arg_name as ax.plot don't have a fmt arg as plot_date
What the title says.
Unexpectedly i've also just discovered that the pandas / numpy types are not that "homogeneous" anymore
https://github.com/pandas-dev/pandas/issues/24877
i.e.
df.col1 = pd.to_datetime(df.col1)
is not the same as
df.col1 = pd.to_datetime(df.col1).to_numpy(np.datetime64)
anymore.