Yes, the author uses an elegant, erudite, and instructional tone (how you may expect your wealthy British grandmother to speak). The author also maintains the second-person to enhance the instructional tone, directing his/her writing directly at the reader. This tone is maintained throughout the excerpt.
I believe that the book of folksongs by Arnim and Bretano is significant because it help us understand history.
Folk-songs is a type of song that is based on current tradition of popular culture at the time they're written.
Which means that from the lyric alone, historian could understand social issues, tale of heroes, and the hardship that people during that time experience.
Appeal means to be attractive or interesting, or to make a serious or urgent request, usually to the public.