From my understanding, the protocols for each of these systems are inherently coupled to the internal service characteristics. RabbitMQ and Kafka take very diff

From my understanding, the protocols for each of these systems are inherently coupled to the internal service characteristics. RabbitMQ and Kafka take very different approaches to messaging. Neither is generally better, and they each make different tradeoffs. These tradeoffs have real impact on client logic. And in this case, where it's not as simple as a line protocol like http, it may be hard to disentangle the "objects" and the protocols. With that in mind, I'd choose the one which is most similar to your internal messaging service so there's less impedance mismatch.