Adaptation of folk tunes to "learned" contexts is almost as old as Western music, in the 15th century it even was one of the main genres, notably in France and present-day Belgium, but also in other countries including England. Quite a number of folk songs are only known today because of such adaptations. Are they folk? Probably not, but they were often sung by non-professionals for their own pleasure. In later times, chorals of the Lutheran tradition, i.e. real folk songs, were the spine of Protestant church music. In Bach's cantatas and oratorios, the whole parish was supposed to join in singing the chorals.

Many classical composers wrote nice arrangements of folk songs in the "pastoral" taste. Beethoven with his English songs is just one out of many. Bartók is the father of modern folklorism; he inspired RVW and the others.

Most of all that music was meant to be executed by amateurs, but professionals perform it as well, in concert halls an on CDs.

Summary: not much news; label it as you please.