Component visual tests answer whether a bounded UI unit rendered as expected for a supplied set of props. That is valuable. It is also different from asking whether a real user can complete a real journey.
Authentication, routing, feature flags, API data, global styles, localization, and layout composition all live outside an isolated story. A component can match its snapshot while the product page is unusable.
Use both layers for different failures
Use component tests for fast, broad feedback on design-system primitives and reusable states. Use full-flow visual verification for the authenticated journeys that determine whether a release is safe.
A flow should carry its own context matrix: admin and member, light and dark, priority locales, empty and full data. Capture the real output in CI and review only changed results.
The goal is not to replace Storybook or Playwright. It is to connect their blind spots to a release decision with visible evidence.