ESBs historically required a domain-aware object model (when I saw them they were routed based upon rich types and terms like CORBA and RMI were still in vogue). This is more obvious when you look down the page for features in Apache Camel and they mention different data type support. Well, a workflow or orchestration engine doesn't need _any_ idea of your business layer data model to make decisions on where they need to be broadcast, but it's a convenience similar to listening to specific topics and segments in Kafka after querying a data broker service. Decoupling routing and representation of objects means that the bus is now dumb but the scheduler / router is now interchangeable. Which is how we can see so many possible competitors to Conductor and EBPM and all that now as shown in these comments.