Im no lawyer, but an API is the most creative part of an entire developer ecosystem to my mind. not the implementation. What made Cocoa so joyful to work with

Im no lawyer, but an API is the most creative part of an entire developer ecosystem to my mind. not the implementation. What made Cocoa so joyful to work with while years of previous Java and MS coding were dissonant painful experiences? All of them manage to get a button on the screen, respond to user input, etc. The naming and organization of different features in a clear and developer friendly way is entirely the API spec. Whether you should be able to protect such a creation from copying is an issue for society to choose. So far it has chosen poorly.