I don't understand your analogy at all, but I believe the principal difference is that a code-generated container is a final, closed thing — it is not, for exam

I don't understand your analogy at all, but I believe the principal difference is that a code-generated container is a final, closed thing — it is not, for example, composable at compile time, so it doesn't fit into a larger type ecosystem. For example, you could write a Vec<T> and instantiate it for Vec<string>, which is fine, but then a different package may want to declare func sort<T>(values Vec<T>). Maybe one is an app and the other is a library. How do you now fit the two together? If the tool is smart enough and both of them are generated at the same time using the same tool and module files, it might work, but I don't think there's anything like this for Go right now, and either way, you have the "same tool" problem.