>> some teams are just not permitted to contribute to OSS in any way
My understanding is that by default you are not allowed to contribute to open-source even if its your own project. Exceptions are made for teams whose function is to work on those open-source project e.g. Swift/LLVM/etc...
I talked to an apple engineer at a bar years ago and he said they aren’t allowed to work on _anything_ including side projects without getting approval first. Seemed like a total wtf moment to me.