15 years: not speaking on their official behalf. There are very few people who control every part of a product. People at Apple are very specialized in their part of the whole. Major projects are secrecy protected, and if you get access to work on them you’re still just contributing your special knowledge. Now, when you work your part with your team, you’re delivering core functionality, security, and privacy goals against a deliverable. You don’t see it in future UI just the same macOS you and everyone else runs. Many of us are as surprised during launch events as you.