I was going to use the Michaelangelo example but it's been taken.

I think the point is that if a person is able to write a song that addresses someone else's point of view, then that person is doing their job... being a writer. Unless that person writes a song that they're disappointed in. Then, that means they haven't done their job.

A good writer should be able to write about anything effectively. If they haven't, then they just haven't done their job. Not that that justifies writing tripe that passes brilliantly as a commercial song.
They must write something GOOD that passes as a commercial song.

It's all very simple. (yeah... right.... )