I've seen a couple news sources that are altering their publish dates to show near the top of news feeds. Google will announce "3 hours old", despite being weeks old.
Even if updates are mostly minor corrections or batch updates of boilerplate, the capability exists to rewrite any part or all of a story if there's no way to see past versions from third-parties from a single cache from archive.is or possibly archive.org.
Archival navigation and visualization should be deeply integrated into a user-centric, privacy browser.