[mystifyingpoi]

This is extremely niche. 99.9% of Kubernetes deployments will never need such nesting. It could be useful for testing tooling (I guess maybe operators?) without recreating the "top-level" cluster all the time.

Also it's a fun idea. Sandbox in a sandbox.

[dboreham]

I've seen many bugs get to production for the lack of such testing.

[never_inline]

Or you know, you can architect around testability from the beginning, where multiple branches / instances of same application can run in the same cluster - in different namespaces.