I used to defend Wagner, but I think focusing on the man is the wrong thing to do. The music itself is the problem. You cannot hear Gotterdammerung or die Walkure without having a certain philosophy arousing. Even Parsifal, in its choice of depicting the blindness of mankind to evidence and beauty before their eyes, is bleak and crushingly aggressive. Of course it is important to be confronted with such things and absorb and judge them from first hand experience, but the music speaks for the man.I recently heard of a book which I've got on order: Wagner: The Terrible Man and His Truthful Art. The title should be self-explanatory.
I make an exception for the opening chorus of Meistersinger. Now that is pure, unabashed optimism the kind of which gives you hope for a lifetime, but even that opera becomes about competition.