A campaign’s ‘Team’ refers to that campaign only. Someone can be on the sub-campaign team and not on the main campaign team, allowing organizations to divvy campaign permissions to users in whatever way works best for them.
Someone with editing permissions and above on the main campaign team control settings for all sub-campaigns under that umbrella, but someone on the sub-campaign team has permission for that campaign only.
Every organization profile, main campaign, and sub-campaign has a ‘Team’ menu in the navigation menu. See who is on the team by clicking here.