This is a huge redflag.
It's basically admitting that you expect most later employees to not understand k8s or how its being used. You may think they don't need because it works, but you have to think about what happens when it doesn't work.
The shops I've been to all had the same mindset: the docker/k8s infra was setup by one guy (or two) and no one else on the team understands what's going on, let alone have the ability to debug the configuration or fix problems with it.
Another thing that might happen is some team members understand just barely enough to be able to "add" things to the config files. Over time the config files accumulate so much cruft, no one knows what configuration is used for what anymore.