And if that spell came at the cost of thousands of lives in forced labor, the monolith dominated the country side, and turned out to be a minor first level spell? What then. But 4e DM's would never do that. They would introduce some super spell off the level charts at a new level of power. The idea that some geeky repressed person trapped under the status quo is the source of the most powerful spell is gone. Players will assume the person is secretly receiving instructions or that they dug it up somewhere.
In fact what is the best promotion that a 4e party can offer any NPC. That's right. Membership in the group. Nothing more. No longer are the phrases like "king maker", "discoverer of", and "inventor" heard. But I bet you they can talk for days on end about how things are fine they way they are, and one should learn to appreciate what they have, and even that these thoughts are dangerous and I should be stopped.