“Manage All Patterns” links to the legacy reusable blocks interface from WordPress 6.2 and earlier – a standard post type management screen that some developers prefer for familiarity.
This interface automatically presets new patterns as synced patterns and provides the traditional post management experience. However, the main pattern interface in the site editor offers more comprehensive functionality.
The legacy interface exists primarily for backward compatibility and developer preference. For most workflows, the main pattern management interface provides better integration with the modern block theme development process.
Understanding both interfaces helps when working with teams or legacy projects, but the site editor’s pattern interface represents the current best practice approach.