None of the parks is thematically flawless, but that doesn't change their status as theme parks. What does the alien planet of Pandora have to do with animals, beyond a vague conservationist message extrapolated from its pro-environmental themes? Since when do Monsters, Inc. or Buzz Lightyear have a thing to do with our dreams and visions for "tomorrow"? Arendelle may have been inspired by Norway, but it has never been and will never be Norwegian. Hollywood Studios actually has it the easiest, because arguably any character or setting that ever appeared in a movie is fair game, but it's still a mish-mosh of disjointed IPs, from space operas to Pixar animation to puppets.
At the end of the day, they're all theme parks: imperfectly so, but theme parks just the same.
Are you saying that you believe Animal Kingdom is the only one that qualifies as a theme park? Or pointing out that Disney brands it as "Disney's Animal Kingdom Theme Park"?
The reason is they added in "theme park" so people don't think its a zoo. But, having said that, Animal Kingdom is the closest to cohesive and thematic perfection of all the Orlando parks, with only Chester and Hester's being a tacky standout.
Well, I'd rather have none of them have "theme park" tagged on in the branding. But I already gave the reasoning - they attach "theme park" in some of the branding to distinguish it from a zoo. The park's official name is still "Disney's Animal Kingdom" and not "Disney's Animal Kingdom Theme Park"