It's perfectly sane if their team already knows how to use K8s, especially if they use a hosted solution like GKE or Digitalocean K8s. (I'll admit that I'd never want to manage my own k8s cluster.)
Once you know K8s, it's not very difficult to use. Plus, it provides solutions to a lot of different infrastructure-level problems.
Once you know K8s, it's not very difficult to use. Plus, it provides solutions to a lot of different infrastructure-level problems.