In 2005 Google search got into a sticky spot, where they were completely unable to deploy new versions of the search engine from the master branch of the code for a while, because there were performance regressions that nobody could find. Deployment and related things like "deploy a copy of the production configuration to these spare 2000 machines" were manual slogs. I was the noob on the team doing such important yet unfulfilling tasks as "backport this Python performance testing script to Python 1.x because our only working test environment doesn't have the same version of Python as production does". This was before borg aka kubernetes, and let me tell you, a whole bunch of stuff was dysfunctional and broken.

All this is not to say that Kubernetes is the right solution to your problem, or to almost anyone's problem. It was just an improvement to Google's infrastructure, for the sort of problems that Google had. For some people it makes sense... for you it might not.