I've been there for the addition of, initial heavy investment in, slow decline of, and eventual removal of Storybook like 6 times across as many companies. The only places where I've seen it work are places that are so steeped in process that they move at a snail's pace. It's not unlike automated UI tests. Someone gets a bee in their bonnet to add it. They do a ton of work to get it off the ground. It looks really good and seems really valuable. And then it becomes a maintenance hazard that falls out of sync with the codebase within the week. Sorry Storybook, but never.