Idk but when we talk about the changes 4Kids did to Yu-Gi-Oh! DM, I never read/hear someone talking about how 4Kids changed Atem and Yugi's relationship.
Their original relationship is a soulmates one (I'm using this term regardless of the romantic connotation that can have), they explicitly talk about how they want to be with the other forever, how they feel they are complete together, how empty they felt when the other is not there. This is what makes the final more emotional, because they don't want to be separated but they have to. And also the fact that they are like soulmates is a crucial part of the original story, it's the reason why Yugi became more brave and confident, and the reason why Atem became more kind and even happy. Their connection is too special, to the point of them having nicknames that illustrate it: Atem calls Yugi "partner", and Yugi calls Atem "my other me". These nicknames represent the core of their relationship: They are SO connected to the point of feeling they're one person, they need each other.
Now, the 4Kids version changed a lot of this. Starting to the fact that they don't use the nicknames, instead Atem calls Yugi just"Yugi" and Yugi calls Atem "Pharaoh". Also, 4Kids heavily changed a lot of dialogues that are about their relationship and how connected they feel with the other.
Ex. Episode 52. In the original, Atem and Yugi were talking about personal stuff but they focused on the fact that they want to be together, Yugi is actually scared about the idea of not being with Atem. So, Atem said "I want to be with you forever, I don't care if my memories never get back", and Yugi said "I also want to be with you forever, I'm willing to give you all my memories" In the 4Kids version, they were only talking about "a new villain" and "how can we stop them?" and things like that, and the scene is supposed to be about Atem cheering Yugi on like a teacher with a student.
And this is how the 4Kids version of their relationship is: They are like teacher and student but Atem is always the teacher and Yugi always the student. It's not a reciprocate one like the original (bc both learned things from the other), it's kinda one sided. It's more about Atem helping Yugi to grow. In the original, they helped each other to grow. They're equals, that's why their nicknames are what they are.,
These changes messed up Atem's arc and a little bit about Yugi's.