Earlier quoted context omitted.
Because it’s a great idea but for instance the Linux kernel would have to come with documentation that mentions the tens of thousands of authors. A massive undertaking that doesn’t help anyone, really.
Linux is GPL and I doubt it would have tens of thousands of authors if it were not. It would have a dozen proprietary forks.
Why? There's plenty of permissive F/OSS projects with large numbers of contributors.
> It would have a dozen proprietary forks.
Probably, but proprietary forks don't stop F/OSS contributions. They can even be the source of them, as upstreaming everything that isn't secret sauce reduced the cost of maintaining the proprietary fork. A number of the big sources of F/OSS contributions to Postgres are maintainers of proprietary downstream distributions (I don't know that all are strictly forks, since I think the proprietary bits of at least some are using the extension mechanism.)