Nonsense! BY DEFINITION, AUTHORS USE WORDS.
Monet was an artist or painter, not a writer or author.
Monet war Künstler oder Maler, kein Schriftsteller, Verfasser oder Autor.
The same is true of Dali.
Schubert was a composer, not a writer or author.
Schubert war Komponist, kein Schriftsteller, Verfasser oder Autor.
Michelangelo was an artist, sculptor, painter, architect and poet.
Michelangelo war Künstler, Bildhauer, Maler, Architekt und Dichter.
English it doesn't have to be words per see, it can mean "the originator of." Now for older profession their are more specific terms but it would not be incorrect to say that music was authored by some rather it would be more corrected to say it was composed. For newer professions one can author a game (if one work alone) or one can author code. Author is basically a specific term for writers and a general term for "originators"
No, you are right, there is no difference. A German W is pronounced like an English V, and a German V is pronounced like an English F. The letter F did not come into the German alphabet till later, I was once told, and so it sounds like the English F as well. Great ear! But Germans don't say the English W in German much, if at all.