Now this is a discussion I really can relate to--though I've put my two cents worth in in others that have really inerested me, and kept quiet in others because I knew I had nothing to add.
I am a graphic artist, I paint, I draw, I sketch. I have taken part in many discussions about the responsibility of the artist. I think one thing I would consider is the difference between fine art and commercial art. In fine art you need only please youorself, the artist; in commercial art you are trying to sell something. It can either be a product or the art itself. Thomas Kincade, previously mentioned, does nothing to make me proud of being an artist. Norman Rockwell, immensely commercial and very popular in his time, also painted other, far less commercial things. I am thinking of one very bleak but very powerful picture of bodies lying on the ground in Mississippi. Its impact is very similar to that of Guernica. The point here is sometimes work is commercial, sometimes it is not. Everyone has to make a living.   
One very fine artist who is a friend of mine said art should make you think, not tell you what to think. I think that can apply very well to music. When an artist decides, perhaps from frustration, to go ahead and tell viewers or listeners what to think, then the artist risks serious rejection. From what I have heard of the Ronstad incident, I agree with what she said but if I tried to put that message in a picture, I couldn't expect to sell it. Or at least only to a select audience. And if I took it to a gallery it could be turned down and so could the rest of my work.
I think that is what happened to her. Wrong audience. She must have expected the response.