A message queue has one (1) job: to keep track of the already-processed message pointer.

Which Kafka doesn't do. So you either store everything forever (lol) or you write some sort of broken half-baked solution for a message queue on top of Kafka. (Broken and half-baked because you're not going to achieve fault tolerance or consistency without re-implementing the storage layer.)

Now, you're just gonna say that "Kafka isn't a message queue". Well, I don't need half of a solution that isn't even a message queue. Nobody needs that.