Probably the next closest is just plain VMs (and potentially backplane/management layer running on k8s or whatever)
But yeah... Even then each cloud has quirks with Kubernetes and there's still quite a few resources just to stand up a cluster. Kubernetes can partially solve the initial provisioning but you generally need the cluster running with nodes before you can use something like CAPI or Crossplane (so you still need Terraform or Pulumi or scripts or whatever)
Having worked with a similar system, shared tenancy with tenant per namespace is just as bad but in a different way (if you use the classic operator pattern with 1 operator per cluster, you potentially have a massive blast radius). Then there's security...
But yeah... Even then each cloud has quirks with Kubernetes and there's still quite a few resources just to stand up a cluster. Kubernetes can partially solve the initial provisioning but you generally need the cluster running with nodes before you can use something like CAPI or Crossplane (so you still need Terraform or Pulumi or scripts or whatever)
Having worked with a similar system, shared tenancy with tenant per namespace is just as bad but in a different way (if you use the classic operator pattern with 1 operator per cluster, you potentially have a massive blast radius). Then there's security...