> Apple loves to change which tools they ship, too, it at least have for the last few years as system updates were routinely breaking our build scripts at work, mostly when Apple would replace a GNU tool with a BSD tool without warning i think.
It's a licensing issue; Apple has never shipped GPLv3 software. This has been discussed dozens of times on HN.
Of course you can use Homebrew to install a GNU toolchain to your heart's content.