One of the cooler innovations we've seen, and I think we're going to see more of, is the ability to take a non-k8s VM and expose it to the cluster as-if it were just another pod. This would let you schedule and expose RDBMs and other specialized servers through kubernetes while keeping them on a standard VM.
I think that's the win/win approach to bridge the gap.
But I think that doesn't go far enough: I want to provide K8s with a YAML file and have Kubernetes itself go and create and provision a VM for me. I.e, I want to "kill" Terraform. I don't care about a 'fabric' network (although that could be convenient), just give me an IP that I can reach even it if is external to the cluster. VMs could be just one more resource that can be created or destroyed by k8s, just like network-based storage today.
I haven't found this exact use-case implemented yet. If noone else builds it in the coming months I'll probably start doing it.
The base pattern should be pretty easy to modify, although the use case here is very specific.