Then your were lied to (or legal was incompetent). GPL has no way to force anyone to publish internal proprietary source code. Any copyright infringer always has the option to stop distributing. If they want to keep distributing something, they have the option to re-implement the missing functionality themselves.

Well I was there for years, and it seems Apple legal should know more about this as a concern than most, and they clearly didn't lie to us about it being a concern for _them_. (Still consistent with your point: it could be their own fear/uncertainty/doubt.)

Perhaps legal decided the fiasco wasn't worth a protracted court battle, and PR digressions, and foisted the option of re-implementing missing modernized functionality on homebrew/macports, on purpose?

Well, I would tend to trust the FSF’s legal opinions about the GPL over that of Apple’s lawyers. Addidionally, Apple didn’t seem to have a problem with GPLv2, and GPLv3 is no more copyleft than v2 was. Finally, the “might be forced to release proprietary code” story is, while FUD, extremely well-known FUD, repeated for decades industry-wide by GPL naysayers, and would be an appropriate choice for a believable story to tell the programmer employees.

If Apple merely wanted to save on work and dump it all on third-party ports, why not remove packages outright or, for a period of time, make them available as official add-ons? Why, in that case, keep ancient versions as part of the OS? Why remove something as widely used as Samba, which as I recall garnered some criticism at the time? It seems likely to me that Apple has some other reason than that to remove all GPL-licensed packages.