Perhaps that’s because some other message brokers are now being touted as databases[0][1], I remember seeing a thread about it on HN couple of days ago.
Kafka is much more like a distributed file system that has queuing semantics baked in than it is an ephemeral queue that implements some level of persistence.
The fact that you put Kafka and RabbitMQ in the same category sort of makes me feel like you're out of your element, Donnie.
It seems like you have the only good use case for it pegged down. I've worked at multiple companies that really, really didn't understand that putting something into the DB comes with some probability that it'll never come out. The arguments were "but it's a dataBASE, it stores data. They'd never sell this as a product if it LOST data; then it wouldn't be a database..."
Almost none of is remotely accurate e.g. RabbitMQ isn't even a database.