In addition to Rook, Minio [1] is also working to build an S3 alternative on top of Kubernetes, and the CNCF Landscape is a good way of tracking projects in the space [2].
[0] https://kubernetes.io/ [1] https://www.minio.io/ [2] https://github.com/cncf/landscape
Disclosure: I'm the executive director of CNCF, which hosts Kubernetes, and co-author of the landscape.
Anyway, one needs an on-ramp to containers on Google Cloud. And one can't open source the one that one has, which despite being nearly mature enough to own a driver's license, wouldn't really fulfill the precise need that Kubernetes fills without some frontend work. So one writes Kubernetes. An almost entirely different fundamental architecture, by the way, so it's interesting for those who've seen both to compare.
In other words, you're not entirely off the mark even with the generalization.
I remember reading somewhere in the K8s documentation that it is designed such that nodes in a single cluster should be as close as possible, like in the same AZ.
Managing stateful services is still difficult but we are starting to see paths forward [1] and the community's velocity is remarkable.
K8s seems to be the wolf in sheep's clothing that will break AWS' virtual monopoly on IaaS.
[0] We (gravitational.com) help companies go "multi-region" or on-prem using Kubernetes as a portable run-time.
[1] Some interesting projects from this comment (https://news.ycombinator.com/item?id=13738916)
* Postgres automation for Kubernetes deployments https://github.com/sorintlab/stolon
* Automation for operating the Etcd cluster:https://github.com/coreos/etcd-operator
* Kubernetes-native deployment of Ceph: https://rook.io/