I'm somewhat ambivalent about Wagner. He wrote some marvelous music, but I often find him somewhat pretentious and superficial - probably what Nietzsche also thought objectionable. Anyway, I don't listen to Wagner, much.
Here is one of my favourites. He wrote the Wesendonck song cycle whilst staying for free in a cottage on the estate of his benefactor Otto Wesendonck and screwing Mrs. Wesendonck. The passion comes through, I think? (Notice the throbbing undertones.)
Jonas Kaufmann is probably the leading tenor in the world today and my all-time favourite tenor. He is really redefining the way a tenor can sound like. I think it is a general trend these days towards a preference for darker voices, e.g. Kaufmann, Netrebko, etc. I believe that many of the singers of a century ago would probably be thought of as rather shrill, today.
Whereof one cannot speak, thereof one must be silent.
Richard Wagner's great-granddaughter, Katharina Wagner:
Anyway, being Wagner's great-granddaughter, she must also be the great-great-granddaughter of Franz Liszt(*). Stumbling across some less flattering images, I'm personally convinced that this is visually verifiable:
(*) Cosima Wagner, admirer of Friedrich Nietzsche, who transformed Gustav Mahler from a Jew to a Roman-Catholic, was in fact Liszt's daughter - Cosima Liszt: