I’ve never really thought about it, until reading this thread. Shouldnt the effect the music has on a person determine if it is proper or not?
If something is composed by someone who goes to the mikvah before he writes each stanza, with lyrics that come straight out of Tehillim, yet it leads you to get up and gyrate in ways Hashem did not intend for the human body to bend (OK, I am exaggerating, a little, I admit, but you get my point), that is OK because of its source, but if it is composed by a goy while eating a cheeseburger and the music is soothing and relaxing, or gets you to tap your feet to the rhythim, that is no good (assuming the lyrics are not objectionable) because of the source?