Revert the changes in https://github.com/pandas-dev/pandas/pull/21361 - [ ]: Remove check in `core/ops.py` - [ ]: Remove test `pandas/tests/tseries/test_arithmetic.py::TestTimestampSeriesComparison.test_dt64_ser_cmp_date_warning` - [ ]: Reenable test `pandas/tests/tseries/test_arithmetic.py::TestTimestampSeriesComparison.test_dt64ser_cmp_date_invalid` Target this for 0.24? xref https://github.com/pandas-dev/pandas/issues/21152