I've sung in a choir 5 Traditional Songs arranged by John Rutter.
The Girl I Left behind Me
O Waly Waly
The British Grenadiers
Dashing Away With The Smoothing Iron
Folk it ain't. They're arranged to sound classical I imagine, or maybe just because of the arranger's musical training.
Similar thing with Gospel songs arranged in a classical way.
They don't do much for me!