Kubernetes is insanely complex and modular. Just yesterday I was looking at the source code and the code part I knew was replaced by yet another pluggable system. Instead of consolidating into a well-understoof set of features, Kubernetes is exploding with complexity, so it's almost impossible to "build it yourself" for a production environment.
However, there are plenty of companies that will sell you a system, including varying levels of support. You then, of course, have to hire your own DevOps engineers that will deal with the areas the support doesn't cover, which, given the complexity, is still an awful lot. Or you do everything in-house, which means hiring even more people.
TL;DR DevOps engineers won't be out of the job anytime soon. Same for Kubernetes developers.
However, there are plenty of companies that will sell you a system, including varying levels of support. You then, of course, have to hire your own DevOps engineers that will deal with the areas the support doesn't cover, which, given the complexity, is still an awful lot. Or you do everything in-house, which means hiring even more people.
TL;DR DevOps engineers won't be out of the job anytime soon. Same for Kubernetes developers.