In the search box where you can “Specify people, teams or apps allowed to push to matching branches. Required status checks will still prevent these people, teams and apps from merging if the checks fail.”…
If I enter an person’s name, it comes up as expected
If I enter a team’s name or slug, it does not
Furthermore, if I try to create this restriction outside of the UI (via API), it does not seem to do anything (and does not error).