It should be possible to have an escalation policy owned by a team without all of the people being added

We want to have our engineering managers group be a last line of escalation, to handle the cases where the on-call engineer is missing, so they can find someone else to assign.

This means that all engineering managers end up being part of all teams (because the escalation policies are owned by the relevant teams.)
This pollutes the interface, they can’t see the services that are part of their actual team, and also grants them access to manage other teams services, which is a security risk.