Yeah, but I think he was mentioned before (and he shows up in most of the guards books). Vetinari is awesome in kind of an obvious way, but he’s not very relevant outside the city. (Well, except for a few treaties with dwarves and the like.)

In contrast, Granny (and sometimes the other witches) arguably saved the entire world several times. There are other characters who do that, but it’s more... luck I guess. The witches actually know what they’re doing, and work hard to achieve their goals.

(For example, though it’s never explicitly said, I got a very strong suspicion that Granny remained a life-long virgin specifically because she expected that it might be useful against unicorns.)