National anthems are tricky. Few are as good as La Marseillaise. Australia got rid of the irrelevant and awful God Save The Queen, and replaced it by popular vote with the nearly-as-awful Advance Australia Fair, a terrible late victorian song by one of those types of poets who thinks "our home is girt by sea" is more poetic than 'we live on an island". Most of the verses had to be removed, and several lines changed - including the first one - to make it suitable for the 20th century. Most people have no idea of the lyrics of the second verse, so it's reduced to an embarrassing mumble until it gets back to the chorus. I think Waltzing Matilda was rejected because a song about sheep stealing and suicide while fleeing the law wasn't the best thing for state funerals.