pymongo 4.0+ hello.isWritablePrimary always returns True even when run against secondary instance

pymongo 4.0+ hello.isWritablePrimary always returns True even when run against secondary instance

        doc = client.admin.command('hello')

        result = doc['isWritablePrimary'] 

This does not happen when running db.hello() via mongo cli. This behaviour also does not happen in pymongo-3.12.3 but does happen 4.0+

Some of our scripts rely on this critical flag to validate primaries and failed when using pymongo-4.0 to pymongo-4.1.1