I'm going to use Oxide console [1] as an example because it has a really good setup of MSW + OpenAPI autogenerated mocks (which means that it doesn't need any complete running backend, just a defined contract).
Consider this fairly simple page [2]. If I'm using the Storybook pattern, I'm keeping all of the state outside of the component, which means I now have to manually memoize every single variable defined before the return to make sure that the component doesn't do any unnecessary re-renders. This includes `intervalPicker`, `commonProps`, `setFilterId`, every return of `useDateTimeRangePicker`. With MSW I have benefits of not needing the API as well as developing in the context of a real production app, using the same exact mocks for unit tests and development.
[1]: https://github.com/oxidecomputer/console
[2]: https://github.com/oxidecomputer/console/blob/main/app/pages...