I always prefer BSD or even more permissive licensing.
If someone can then sell a proprietary version, they might be willing to
submit a module with the same kind of licensing. No guarantee of that,
of course. But why not?
There is something else that does happen. Companies close. People
retire. A contract for their software may end. Sometimes people die.
This actually happened to me during one project.
All of their proprietary software may suddenly become available with a