Why Don't The Icons Have Names?
Why are they just: "the Dragon Emperor" or "the Diabolist"? Wouldn't everyone know their names?
What if the power invested in the office of an Icon requires you to strip yourself of your identity to immerse yourself in your new position? What if individuals spend decades of their lives erasing every scrap of knowledge of themselves before ascending to Icon status. Never having close ties, mind wiping or eliminating friends, family and rivals?
The Secret Source of an Icon's Power?
What if learning the facts of an Icon's life, their name, their homeland, their deeds--gives you power over an Icon, make them weaker in your presence? What if publishing this knowledge might cause an Icon to fall, become more mortal, less legend?
What if the personal details of your favorite Icon are in play? What if in order to stop an evil Icon you have the chance to crush their legend first? What if you stumble upon the secret history of an Icon's life and find them now bent on your destruction?
Having a figure that's only known by a title is mysterious, but just giving them a name removes a lot of the mystery and seems like a bit of a let down. This way there's a tidy in setting reason why all these Icons have enigmatic aliases and no one can tell you their real name. It's a mechanism that lets you dole out precious (and dangerous) bits of lore for players who love to dig into secrets, and the secrets feel dangerous and forbidden. It gives GMs some real consequences to bring into play, for them to make some good drama out of.