There's a project idpbuilder that helps setup ArgoCD projects and a gitea server for you as an artifact registry as well. Regarding operators, Strizmi or Bitnami Kafka one are most common I've seen used, though confluent has one. I'm not sure if AutoMQ, Pulsar, Buf or Redpanda have one yet. The Kafka ecosystem is fracturing in the cloud native space.
I don't touch postgres much, but there's multiple operators. Like I said, serverless offerings are often used in enterprise, so maybe Amazon ACK rds or aurora operators, if not Crossplane