Incorrect. Features available to users still require a minimum, standard level of support. This is like the deceptive misnomer of staging and test environments provided to internal users used no differently than production in all but name.
If the feature is in the code that's downloaded, regardless of whether or not the build process enables it by default, the code is definitely being shipped.
This is an insane standard and attempting to adhere to it would mean that the CVE database, which is already mostly full of useless, irrelevant garbage, is now just the bug tracker for _every single open source project in the world_.
Why is it insane? The CVE goal was to track vulnerabilities that customers could be exposed to. It is used…in public, released versions. Why wouldn’t it be tracked?