If your goal is to show strictly that technical things can be produced by cooperatives, yes. If your goal is to show successful businesses that pay the bills of everyone involved through their technical labor, perhaps not.

There are examples of successful co-ops outside of tech: Mondragon, REI, and credit unions like Alliant come to mind. The absence of co-ops in tech could just be because the model hasn’t been tried yet. It doesn’t provide any signal about the viability of the model, or lack thereof.

You're absolutely right - the world is full of cooperatives! REI, every credit union, Vanguard, and State Farm all spring to mind.

With that said, might some consider it noteworthy that these are primarily customer-owned cooperatives rather than worker-owned ones? That seems like it might not be completely inconsequential, but perhaps I am being excessively picky.

Please accept my apologies for being less than entirely clear. It is my opinion that FOSS projects are unlikely to be considered good examples of worker-owned cooperatives that are also successful businesses. As you say, this offers no comment in any way on the viability or suitability of the model.

A quick search suggests that the worker-owned cooperative model is being tried! https://www.techworker.coop/

At a corporate level I cannot think of a single co-op that is owned by its employees at this scale.

Mondragon is worker-owned.

Not unless they make money and that money is distributed to the contributors.

So no.