It depends on the work. Sometimes people have to really be tight like a rock band, sometimes more freelance like the horns in an orchestra.
A rock band is a team in the sense I use it, whereas five musicians playing similar instruments to a score aren’t. There is a reason sports teams are almost always less than a dozen (The forwards and backs in rugby are each a team).
Sometimes you need a team to be effective, sometimes you can be a looser tribe. I have a hunch with no data that transactional work like a factory can be done by a loose tribe, but knowledge work has to be collaborative and collective, and requires a tight team to be effective.
[Newsflash: Jurgen Appello is convincing me of the viability of a tribal model here
This also seems relevant: 5 things that make teams teams.
- explicit shared goal
- specific form and workflow
- internal norms