But you add k8s now, so that three hosts can orchestrate three other hosts. Success!
We seem to be obsessed with producing the most complex machines we can instead of creating simple, understandable machines.
It's not solving "your system went down", it's adding more layers of system that can go down.
Are you really trying to suggest that people can't use Kubernetes to increase their reliability?
I'll take "more configuration in yaml" over that.
Leave your nice clean K8s deployment paradise to cruft up for decades, and will it be any better? I doubt it - there'll be old Dockerfiles and weird bits of yaml that shouldn't work but do, and upgrading a version of anything will break random things.
So yes, I think I would prefer the decades of crufty perl and bash to decades of crufty outdated yaml. At least the bash scripts have a hope of doing what they say they do, and are likely to still execute as intended.
One can certainly create an HA cluster over some infrastructure set up by kubernetes, just as well as one can take a bunch of physical servers, set them up by hand, and create an HA cluster with them. K8s isn't adding anything to the availability.