>Running five node zookeeper cluster was pure overhead.

I have not experience this issue. I run a 5 pod ZK in K8s with each pod's memory: 256Mi & cpu: 0.1 for a couple hundred thousand messages a second with Pulsar.

I think 1.5 Gi and half a core for handling quorum & metadata locking for a stream storage isn't exactly what I would consider overhead. It isn't like deleting ZK tomorrow will not mean that Redpanda doesn't take on the additional resources itself.