> unless they provided the OS-level signing keys on request All they need is to provide a bypass which permits executing a modified binary, which they already

> unless they provided the OS-level signing keys on request All they need is to provide a bypass which permits executing a modified binary, which they already do otherwise projects like Homebrew and MacPorts wouldn't be possible, not to mention the fact that development on macOS would become a nightmare. From a technical and legal perspective there's no reason to avoid the GPLv3 for a program like GNU Make. Apple's lawyers are just lazy and instituted a blanket, company-wide prohibition against GPLv3. A GPLv3'd Bash might plausibly create some headaches given the system integration, but they could have always used ksh like every other BSD, or zsh as they're now doing, as the default system shell and shipped a modern, updated Bash as a convenience for user scripts. iOS also poses additional headaches, but that's a separate issue--Apple already deprecated system(3) and in general you can't (and don't) rely on shell programs in iOS. TL;DR: Apple's lawyers are lazy and needlessly hostile, even given an expansive, unrealistic interpretation of the GPLv3 anti-circumvention clause.