It is well-known that
A extends Copyable
First of all, I disagree with people saying that
Cloneable is "broken". It is not "broken" -- it does exactly what it is documented to do, which is to cause
Object.clone() to throw an exception or not. People don't like it because they assume it is something it isn't -- they assume that it is an interface for objects that can be cloned, which was never what it was supposed to be for.
Java (still) does not have an interface in the standard library for objects that can be cloned. It would be nice if they added such an interface, but they haven't. You could make your own interface, and you can make your own classes implement it, but the problem is that you cannot make existing standard library classes implement it. So that would only be useful if you were only dealing with an ecosystem of your own classes.