Why is it wrong to say slurs?

I am from a country where there exist no taboo words, like there are in America. I understand why it's bad (even taboo) to use a slur in a derogatory sense. I'm wondering about two context where I don't understand why saying these "bad words" out loud is bad.

Why is it bad to say a slur when discussing it? In that context it's obviously not derogatory, why is it bad? There exist a clear distinction in meaning when talking about the concept that the word refers to and the word itself (contrast "i eat cheese" and "cheese is a germanic word"). Why is it bad when you aren't even referring to the taboo concet.

Why is it bad to say a quotation with a slur in it? This goes for books and songs. Why is it bad to sing a slur out loud, especially when the musician actually says it.