Madonna's music was seen as undersirable (it wasn't all that good anyway ). I had one of her CDs, and an elder visting my home was visibly displeased when he saw it on my CD rack.
There was a lot of talk about Thriller - don't buy the album, don't watch the video. I remember several discussions by Witnesses about that disc and the title song especially.
It's not just jws either. I remember a letter to the editor of a local newspaper written by a "Christian" who objected to Bennie And The Jets by Elton John, contending that the lyrics fomented teen rebellion. Perhaps the letter writer was a jw, but it could have been any fundamentalist.