The documentation is tagged as “Experimental” which is one of our ways of saying that we’re either not working on this feature and don’t recommend using it for shipping your game unless you plan to maintain it, or that we are working on it but it’s not in a shippable state right now for the current release. In this case, it’s the former.
We don’t specifically mention on pages, beyond “experimental” or “beta” status, because it would be a significant chore to maintain more detailed plans on each page and should we miss something that can lead to further confusion and expectations. It’s better for the documentation to be more strict in defining expectations of these features with “Experimental” and “Beta” definitions.
This is a feature that we want to revisit for development in the future, however, there is other work that has a higher priority at this time.