> In all seriousness I'm sure this is useful in limited cases, but for most the right answer isn't some fancy UI, its middleware or some layer on top of kubernetes that allows you to automate away the toil-y parts of YAML, but keep the flexibility.

I think Dhall is in the right category of solutions for this problem. YAML needs to be reusable and text templates a la Helm are an amusingly bad solution. Moreover, I think static typing is a very nice feature for things that generate YAML since it’s so easy to make mistakes with these kinds of tools. I’ve used Starlark for these kinds of tasks in the past and the lack of static typing has been a sore point.