Such a broad statement without examples is not helpful.
Here are some lyrics from a song done by Third Day, one of the groups mentioned in the article. Please tell me what you consider to be "unsound" in these lyrics.
Holy, Holy, Holy, are you, Lord God Almighty. Worthy is the Lamb; Worthy is the Lamb; Worthy is the Lamb. You are Holy, Holy, Holy, Amen.
(most) modern songs. Third Day is good stuff.