Didn't watch the game or the flubbing of the national anthem for the record, but Imo the anthems should be sung by people other than pop stars, maybe someone from the forces, choir or just a regular "Joe(Jo-Anne!) off the street. As mentioned, it's not meant to be a means to promote someone's carreer, it's meant to honour your country and the people who sacrificed dearly for the freedoms inherited by us.

Half of communication is listening. You can't listen with your mouth.