Well thought out response, and you may be right. But, what if your first paragraph is true?
The story about African Christians may very well be true. But, does that mean that just because pagans use syncopation in their tribal worship that no one else can use it? That to use syncopation in a song is sinful?
How do we know that syncopation wasn’t used in ancient Israel? We have no idea how their music sounded. The earliest treatises about music and its affect on people come from the Greeks (at least that’s what I’ve read). They point out how certain modes of music affect people emotionally. There’s no doubt about it that people can be manipulated emotionally with music - but, does that mean because that’s possible that we shouldn’t ever use music in worship or that it should never have emotion? No - but we do need to be aware of it.
My biggest problem with any Christian artist today is not so much the style but what are their motives? I hate the “marketing” of Christian music that goes on today. Many Christian artists are treated and promoted just like secular rock stars. But, what I wonder about is what is their personal life like? Are they living a Godly Christian life? Is their ministry all about them or serving Christ? Of course, this should be the concern of all Christians - not just musicians.
Anyway, I’m more concerned about the witness of all Christians in their personal and professional lives than with what style of music they use to praise God with. At least that’s my take on it.