Frozen was selected for KH3 before it even released in theaters. Nomura and the team got an advanced screening of the film and liked it so much they decided to include it in the game. That it became a worldwide phenomenon was merely coincidence.
The reason why it was poorly executed was more because of the weird restraining order Disney placed around it, which was not exclusive to KH and was even in effect in Once Upon a Time. I forget who but another member here explained the situation better and suggested this weird treatment of Frozen may have been because of John Lasseter. If that's true, things may be different now after his departure.
Even the same can be said for some of the other KH3 Disney worlds (minus Big Hero 6) besides just Arendelle
@Sign.
In fact, Pixar was also to a degree restrictive with Nomura on the worlds based on their movies (not in the level as
Frozen's or even Kingdom of Corona's guidelines), as literally the majority of the folks at Pixar were all involved with both the Toy Story and Monster's Inc. worlds in KH3 respectively such as Tasha Sounart, Jason Katz and the characters designers from the Toy Story films and Monster's Inc.
It doesn't surprise me, cause apparently it was most noticeable in Monstropolis as Pixar was VERY Picky and restrictive on that world according to an
interview from Nomura and in the Ultimania when compared to guidelines put on Toy Box, which would likely explain why Randall wasn't even fought as a boss.
San Fransokyo (Big Hero 6) I'd say was the ONLY new Disney world in KH3 that Disney didn't put guidelines in compared to Arendelle, Kingdom of Corona, Toy Box and Monstropolis as that had to do with Roy Conli having San Fransokyo's story being an original story set after the events of the movies
I don't think Disney was really restrictive in the previous KH titles prior to KH3 as they didn't put guidelines in the different Disney worlds that appeared in the different KH games such as Halloween Town (Nightmare Before Christmas), Neverland (Peter Pan), Land of Dragons (Mulan), Pride Lands (The Lion King), Agrabah (Aladdin), among others, and the creators who worked on the films weren't involved in the KH games either.
It's easily the reason why Olympus (
Hercules), 100 Acre Wood (
Winnie the Pooh) and The Caribbean (Pirates of the Caribbean) where the ONLY Disney worlds I didn't see ANY restrictions/guidelines put on them by Disney for
Kingdom Hearts III, especially the former two. This is given as as I said, most of the people who worked on those films weren't involved in the game and Disney who had no involvement with those movies the world is based on from the previous installments (
Kingdom Hearts, Kingdom Hearts II, Birth by Sleep, etc.) just allowed Nomura and his team to do what they want with these worlds based on those specific Disney films given that they appeared in previous titles, and the same can be said with the other Disney worlds in previous KH games I mentioned above.
Not sure if Arendelle in KH4 will be any better than it was in KH3. If Disney is still restricting it I fear for the worst. Anna and Elsa may not even remember SDG, lol
If they can fix Port Royal/The Caribbean's problems from KH2 and made the world a thousand times better in KH3, then I can expect the same thing for Arendelle in KHIV.