This is what I use and it applies to all other groups except Staff and Team.
PS: sorry for resurrecting “zombie” posts but other people might still find it useful.
body:not(.staff) #topic-footer-buttons .pinned-button,
body:not(.primary-group-team) #topic-footer-buttons .pinned-button{
display: none;
}
body:not(.staff) #topic-footer-buttons .pinned-button:not(.is-hidden)+.topic-notifications-button,
body:not(.primary-group-team) #topic-footer-buttons .pinned-button:not(.is-hidden)+.topic-notifications-button {
margin-top: 1em;
}