If we want to completely clear in the object copy lesson, we can include a snippet that mentions string interning, where since strings are immutable, only one instance is stored in memory and any future references to that same string can be referred to the singleton in existence. So yes, primitives are "copied as a whole value" in behavior, but it's a little bit more complicated than that if we get into implementation detail.

Is this too much? Thoughts? JavaScript.info seems to be a pretty thorough resource, so I can definitely see it including this kind of detail.