What's the general thinking around putting private identifiers (eg user name) in kube labels? That data would be going to a monitoring stack, eg Prometheus or hosted Cortex?
kube-state-metrics does its own service discovery and outputs prometheus metrics that it cares about, but any app could do that.
I wouldn't necessarily put _user_ data in labels, but team/product names and contact info of the coworkers responsible for the service seem fine to me.