You are talking from the perspective of Rust. And you are right that in Rust, it cannot/should not be the same!
However, if you forget about Rust specifics, then things look different. E.g. by simply having the constraint of complete immutability, there is no reason to differ between an object identity and its deep content anymore - it will just be always the same. Of course that means no mutation and hence reduced performance for certain things, which is why Rust doesn't do it.
However, if you forget about Rust specifics, then things look different. E.g. by simply having the constraint of complete immutability, there is no reason to differ between an object identity and its deep content anymore - it will just be always the same. Of course that means no mutation and hence reduced performance for certain things, which is why Rust doesn't do it.