A conventional keyword-based search engine is unlikely to actively and subtly encourage a user to (A) reveal secrets and blackmail material (B) become entrapped

A conventional keyword-based search engine is unlikely to actively and subtly encourage a user to (A) reveal secrets and blackmail material (B) become entrapped in behavior the Current Authority will punish them for. A better "some of this isn't new" comparison would be to imagine you're communicating with an idiot-savant human employee, someone can be tasked with hidden priorities and will do anything to stay employed at their role. What "old" threats could occur there? That makes for a rather different threat-model.