Currently on Access Control creation, the cluster drop down menu is showing all clusters:

This should only show clusters where the CNV operator is installed/running. jpacker@redhat.com provided this additional context as well:

On the which Cluster to show, MTV has been using a label open-cluster-management.io/cnv-installed: true

We are using that for now, because that is the label I used in the policy I contributed that allows you to install CNV & MTV on ManagedClusters (we need to have a discussion about this aspect of the solution for 2.15, how CNV gets there). 

It sounds like we still need to decide on how to properly implement this. jbanerje@redhat.com and jpacker@redhat.com are good resources to help with coming up with the right solution.

Slack thread for this discussion: https://redhat-external.slack.com/archives/C08AJ4XMVGB/p1749228807002899