Fifteen years ago, Apple delivered a fast, good-looking, easy to use operating system with a solid Unix foundation that ran on great hardware. Developers flocked to it and evangelised Macs and OS X wholeheartedly to friends, family and colleagues. This toehold in the market was a significant contributor to Apple’s now near ubiquity outside the enterprise. What if Apple’s developer tools developed a reputation for being slow, awkward, capriciously broken, unfixable—and getting worse, not...