So, I guess the question is ‘What’s the point of the National Anthem being performed at a sports event?
Is it;
A) Just for entertainment
or
B) A mark of respect/nod to tradition/pride/celebration of country etc and an opportunity for everyone to sing along as one, regardless of team allegiance
If it’s A, then an artist mixing it up is fine. If it’s B (or a similar theme to B), then it needs to be done in a way that the crowd can sing along, so needs to be as close as possible to tradition.
Personally, I think National Anthems are about everyone singing along together (those who want to anyway) and shouldn’t be messed with - they should be a symbol of national pride etc
But equally, understand many people don’t like them, or take offence to certain elements, but think that’s a different conversation to somebody ‘jazzing up’ a national anthem.
For me, it’s all about the crowd singing along and a bigger sense of belonging, despite difference in team allegiances.