Well, if they frequently incorporate Nazi imagery into their artwork and then begin to openly express doubts about the Holocaust, then hell yes it matters.
This is actually quite a sad story, because [write adopts cheesy Sigmund Freud accent] I think it highlights one of the occupational hazards of the “artistic temperament,” which is an overfocus on being a provocateur or pushing the boundaries. Under this mindset, ideas that are discredited or just plain wrong can come to be seen as outré and thus embraced. This leads to a self-induced sense of persecution and isolation as the artist is shunned for his/her beliefs, thus clinging more tightly to the same beliefs because ostracization = validity. [Writer drops cheesy Sigmund Freud accent.] I’ve seen it happen, people. You’re out there on the edge and you’ve got to keep going further and further until you’re a holocaust denier, an Objectivist, or, worst of all, a Juggalo.