Even though he doesn’t proclaim it aloud, Bojack believes himself to be unique in the sense that he is the only sad person in the world. Sad, yes, but he doesn’t go about weeping in the corner of his bedroom. Rather he opts other ways to deal with his sadness and anxiety, like using drugs and acting out. Media thinks he's an horrible old fart in his late fourties', early fifties. Which they aren't at all wrong and he hasn't come to affect that. He's narcissistic, against himself in the head.