I don’t know what a world without copyright does to corporate sponsored open source. It certainly reduces it because there are many corporate sponsored projects that monetize through dual licensing. My guess is in a world where you can’t even guarantee attribution, it’s much harder to convince your boss to let you open source a project in the first place.

So ignoring people who are being paid by corporations directly to work on open source, in my experience the vast majority of contributors expect to be able to monetize their work eventually in a way that requires attribution. And out of the small number who don’t expect a monetary return of any kind, a still smaller number don’t expect recognition.

If this weren’t the case you’d see a much larger amount of anonymous contributions. There are people who anonymously donate to charity. The vast majority want some kind of recognition.

Obviously we still see art, if you greatly reduce the monetary benefit to producing art, you’ll see a lot less of it. This is especially true of non trivial open source software that unlike static artwork requires continual maintenance.