Kingdom Hearts fans are discussing whether Summons like Simba, Ariel, and Chicken Little break the "world order" that Sora, Donald, and Goofy are meant to be protecting.
Although it gets mentioned less as the series goes on, one of the main rules that Sora, Donald, and Goofy have to abide by when they're adventuring across Disney worlds is protecting the "world order". This means that they have to make sure that the worlds they journey to aren't aware of the existence of other worlds, and know as little as possible about things like the Keyblade and keyholes.
This is mentioned by Donald and Goofy in the first game's opening hours and pops up at other points in the series like when the team end up in the Toy Box. As important as this rule seemingly is, there's one gameplay mechanic that seems to get in the way of that idea - Summons. In each mainline game, Sora can call in allies from across the Disney world, both those that he's met and has a relationship with, and some that he's never encountered.
As pointed out by Redditor IllustratorAfter on the Kingdom Hearts subreddit, the whole idea of Summons flies in the face of protecting the "world order". If Sora is calling these characters out from their worlds to briefly help him in combat, surely that's breaking the world order and informing them of the existence of other worlds. Even more so if Sora actually knows them and has already interacted with them in their world.
One Redditor, ScarletteVera, points out that Donald and Goofy's whole existence in these worlds breaks the order as they're clearly not from most of the worlds. However, this is countered by Donald and Goofy's entire existence breaks the world order. This is countered by naynaythewonderhorse, who argues that it's more about not interacting or meddling with other worlds, rather than what the characters look like.
Redditor Heradi argues that the world order is to keep people from getting the "great picture", but that it's futile for most of the worlds and characters as they end up finding out anyway. They suggest that all the Summons from the first game are characters who either offered to help Sora, or whose worlds have already disappeared into the darkness. In Kingdom Hearts 2 and 3, most of the characters are ones who already know or have helped Sora in the past (except for Chicken Little, who is a little out of place).
Although there are a few good theories as to why the world order is so loosely kept, several Redditors pointed out that the rule doesn't really make much sense as, even though Sora, Donald, and Goofy have a good reason for travelling the world, some characters like Scrooge are able to travel however they like with no worries just because he wants to earn money.