Ratatouille on the other hand...

No, I think that's a common opinion. I share it.

I would respectfully disagree. Spoilers ahead for a 16 year old movie.

I think while the rest of the movie has some fantasy elements and requires some suspension of disbelief, it's ultimately about Carl's personal growth and being able to figuratively and literally let go of his wife's death.

Also, when Ellie died, it was like Carl's social life died with her. By the end of the film, Carl becomes a part of the community instead of angry and isolated. In the at way, it's also about a found family with him becoming a father figure to Russell and taking in Dug.