What I mean by DR is that if a data center gets nuked, you still have a replica of your k8's platform running in your other data center(s).

So k8's basically runs a replica of your whole system behind the scenes so if a physical location goes down you still have your system running.

What about all the data in DBMS, file systems, object stores? Also what about BGP routes, firewall settings, SNAT/DNAT rules and the like?

There's a lot more to replicate than just the bits in the apps.

Those are the types of things developers simply don't have experience using. And if Kubernetes tries to replace all of those it will become the new OpenStack.

Yes to all. The most difficult thing is persistent volumes, but leveraging things like Heptio's ark allow you to send them to an alternative storage class. It's awesome stuff.

https://github.com/heptio/ark

Well, that depends where those resources are running and also depends if you're leveraging persistent storage in k8's. All the routes/firewall/dns etc. will be preserved in the event a data center is nuked. Like I said, k8's is replicating your entire system behind the scenes.