Is that intended to be a good example? There's still tons of duplication between the environments.
Kustomize eliminates the vast majority of the duplication (i.e. a unique fact about the cluster being expressed in more than one place), it's just the boilerplate that's annoying.
Not a good one, no. I am currently in the process of rewriting this, so that I eliminate duplicate code. The language has the potential, I am still in the process of learning. I also dislike boilerplate, but I think my example is still better than pure yaml.
Kustomize eliminates the vast majority of the duplication (i.e. a unique fact about the cluster being expressed in more than one place), it's just the boilerplate that's annoying.