Daniel Pfeifer
We wouldn't have a problem of unreferenced commits if we hid the refs instead of deleting them.
I don't suggest deleting any branches in the libraries. I suggest allowing maintainers to delete branches in their libraries.
But why? They don't hurt anything if they're available but hidden.
Therefore, we must assume some branches will get deleted.
Not if we ask that it not happen.
In the superproject, we don't want to reference deleted branches from the libraries, so we delete all branches that might potenially reference a deleted branch from a subproject.
Then you delete all branches, because they all reference subproject branches, and in your world, some subproject branch may be deleted.
If we hide the branches in the superproject instead of deleting them, they still will be accessible, so we would still have the problem, don't you think?
Of course, if you let people delete the branches they reference, yes.
If we hide the branches in the subprojects instead of... what? The only alternative here would be to not allow maintainers to delete old branches. I don't want to force anybody in this direction.
I don't see the problem. They'd merely be archived on GitHub. Nobody would have to be the wiser.