TYPO3 Core

They do not provide any functionality and are merely an example.
They might just confuse editors if the integrator has not cleaned up that field or used them in the frontend.

Keep the fields, though since they serve a role (providing "variants" of a page/content element) and we would like integrators to use them if they implement a "variant" for commonality.

That's breaking, thus provide a .rst how to get the example values back (Configuration/TCA/Overrides/tt_content.php).

It has to be discussed if the .xlf-entries should stay although unused.