"collective product" is correct and can be used in written English.
You can use it to refer to a project, creation, or outcome that was achieved through the combined effort of a group or collective. For example, "The collective product was a success, thanks to everyone's hard work."
It's better to think of Bezos' investments as the collective product of a certain personal attitude.
Work team effectiveness is enabled by team processes that combine individual efforts into a collective product.
Democracy is precious: the collective product of centuries of struggle by our ancestors, and forged amid protests, riots and massacres.
The crops on which we depend -- like wheat, rice and vegetables -- are the collective product of human effort and ingenuity.
Whitney saw the most marked distinction among religions as being between race religions ("the collective product of the wisdom of a community") and individually founded religions.
Because it is a collective product — representing whatever 17 intelligence agencies can agree to — its judgments are, by definition, conventional wisdom.
But one of the strange things about growing older is how twee cliches begin to make sense: the notion of the dead living on in those left behind used to make me particularly cringe, but it's true, we are, in part, the collective products of those we love.
Moreover, plaintiffs' proposed final judgment is the collective work product of senior antitrust law enforcement officials of the United States Department of Justice and the attorneys general of 19 states, in conjunction with multiple consultants.
Quirky, the design collective whose products are often true to its name, has melded milk crate shelving, Lego blocks and hipster design to create Crates, a modular shelving system with dorm rooms in mind.
Today, the European Economic Community's collective gross national product exceeds our own.
It is a collective endeavour, the product of the labour of millions and the support of the state.
