Kafka also provides early architectural scaffolding for multiple teams to build in parallel with predictable outcomes (in addition to the categorical answers to hard/error-prone patterns). It’s been adopted in principle by the services on, and is offered turn-key by, all the major cloud providers.

Personally I’d expect some kind of internal interface to abstract away and develop reusable components for such an external dependency, which readily enables having relational data stores mirroring the brokers functionality. Handy for testing and some specific local scenarios, and those database backed stores can easily pull from the main cluster(s) later to mirror data as needed.