Basically, this is yet another paid packaged Kubernetes distribution, that has the explicit goal to do "Hybrid clustering" so that it is easier to lure the customer back to GKE. Do I get that right ?
Now, the benefit of upstream K8s is that your dev team can build apps and containers without proprietary APIs; so when you are ready to move to the cloud you are not locked-in.
That being said, why would I not use the actual free upstream Kubernetes for my on-prem distribution ? (with the help of one of the thousands installer out there like kube-adm, kubespray, etc).
What I have seen working with Kubernetes for quite a while, is that the lowest common demominator is the YAML definitions for your workloads (what you want to run on your Kubernetes cluster). Those should be portable accross any Kubernetes distribution, on-prem or on the cloud. As far as I can tell, today this is already the case.
Is the benefit in this case that you can use the Google ecosystem for logs etc ?
None of them actually provision your infra for you (VMs, LB rules etc). GKE On-Prem will.
Is it fair to say that this is similar to Canonical Ubuntu MAAS + Juju Kubernetes? I'm sure that Red Hat Openshift must have something similar also to install directly on a pool of managed bare metals.
The workloads will still be as portable as ever, of course.