Reproducing pandas-dev/pandas#56679

Reproduction script

import sys
import pandas as pd

series_dtype = str(pd.Series([]).dtype)
df_dtype = str(pd.DataFrame({'a': []})['a'].dtype)

{
    "pandas_version": pd.__version__,
    "python_version": sys.version.split()[0],
    "series_dtype": series_dtype,
    "df_dtype": df_dtype,
    "mismatch": series_dtype != df_dtype,
}