No it is not. And I don't get why ATRL is so bothered by it.
I mean, Daft Punk is huge and known for this hiding face thing, but still we know how they look like and nobody got a problem with that. Why is it annoying for Sia to do the same thing?
But the most "robotic" stars didn't exactly sell well this year so... Everyone likes manufactured stars so long as they can offer the vaguest fake nod to award some kind of humanity to the cause.