Onward (2020)

The whole movie was, supposedly, based on the director's (Dan Scanlon) relationship with his brother after his father died when he was very young. So the core story about the younger brother seeing the older as his surrogate 'dad' was the story he wanted to tell. The setting and all the character designs etc. was just window dressing.

I would argue that they should have realized part way through that the window dressing was worthy of a somewhat different movie. Perhaps they have intentions of making some sort of continuing story on Disney+ or whatever.