Socratic Irony requires faith, however faint, that truth is worth uncovering, that dialogue can refine us, that ignorance exposed is a step towards wisdom. It is in a quiet way, optimistic. Even Socrates with all his feigned ignorance believed the soul could be improved by inquiry.
The modern cynical subject however has already lost that faith. He knows the game is rigged, the arguments are rehearsed, the participants are posturing.