I'm open to the possibility.

Sorry, I forget not everyone here is a music geek.
If we were just talking about, say, Steve Earle, I'd agree with you; he's a bit of a niche singer and isn't the superstar that Nelson, Cash, Kristofferson, etc. have been.
But do you really think Willie Nelson's fans like him for his views more than his music? Again, this is a guy put on a pedestal by many of the same people who are lambasting the Dixie Chicks. I would say the vast majority of his fans like him
despite his views, not because of them; a consideration they won't give to the Chicks for some reason.