Not every user connected to a project is actually working on it. The Project Team tab makes that distinction clear by separating the two groups.

These are the users actively managing or working on the project. They appear at the top of the Project Team tab so it is always clear who is responsible for what, and they can be assigned an optional Project Team Role.

These users have permission to view the project through their workspace settings but are not necessarily involved in the day-to-day work. They are listed separately below the active team for reference.

Both groups are visible on the Project Team tab, so you always know who has access to a project versus who is actually running it.

Read the full article: What is the difference between users on the Project Team and users with project access?