Pandas BUG: cast_pointwise_result with BooleanDtype and all-NA values

Pandas version checks

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Reproducible Example

arr = pd.array([True, False])

values = [pd.NA]

result = arr._cast_pointwise_result(values)

>>> result
array([<NA>], dtype=object)

Issue Description

We'd expect this to retain BooleanDtype.

Expected Behavior

NA

Installed Versions

Replace this line with the output of pd.show_versions()