With a message broker, you can transmit JSON dynamically to different clients, resulting in “an event-driven architecture.” The problem with this approach is that the creator of each individual “service” in this network mesh needs to anticipate the usage requirements of all future potential clients, for an infinite amount of possible questions, for an infinite amount of time.
This is the equivalent of anticipating every possible answer to every imaginable question that can be phrased using computer languages, and creating a pre-computed list of potential answers. This is not only awkward and sub-optimal, but also impossible, resulting in the internet as a whole becoming a trillion times “dumber” than it needs to be.