For common questions and answers, see Vortex FAQs.
Every node bundle is under the civictheme_editorial content moderation workflow. Core forbids the Publish content and Unpublish content bulk actions on moderated entities, because publication status is owned by the workflow rather than by the status field. The failure is by design and applies to every account, including uid 1.
Use Publish latest revision, Unpublish current revision or Archive current revision instead. These apply a workflow transition and are available to the civictheme_site_administrator and civictheme_content_approver roles.