Do you think it's weird that I was fine with Roxas finding out he was Sora's Nobody in Kingdom Hearts, but Adrien not being what we thought he was triggered my ick factor a lot? Do you think it's because we learned that about Roxas before we had a lot of time to get attached to him?
I was initially going to say that I can't answer this because I've only played Kingdom Hearts 1, so my knowledge of the later games is pretty limited. Then I remembered that my little brother is both obsessed with those games and the Mycroft to my Sherlock*, so I gave him a call and got the expert opinion (and a reminder that I need to play the Kingdom Hearts games so that my brother can talk about them with someone who understands story telling because those games apparently make a lot of... interesting choices.)
Here is the sum of my brother's analysis:
The two properties handled the concept of personhood and artificial beings in such wildly different ways that it would never even occur to him to compare them (though it was an interesting question once posed). A good portion of the later Kingdom Hearts games revolve around asking what a person even is. Should they try to make the Nobodies into people? Do the Nobodies even need to change to be people or are they people already? What makes Roxas different from other Nobodies? These questions start being asked very early on and, for all the story's flaws, you can tell that the writers are aware that they're dealing with a serious topic and that they're trying to do it justice.
Meanwhile, Miraculous introduces artificial beings who don't have true free will and then... completely ignores all of the ethical implications of that plot point. Emilie and Gabriel are good parents. The fact that the heroes have been killing off sentimonsters isn't concerning. Gabriel's commands are just a minor inconvenience to Adrienette and not anything that needs to be explored in a deeper way. He's still totally redeemable and it's fine that Adrien never learned the truth while his father was alive so that he could decide what that meant for their relationship on his own terms.
Given all of that, it's really not shocking that Kingdom Hearts makes you feel invested while Miraculous repulses you because the Miraculous introduced human sentimonsters for cheap shock value to the point where I firmly believe that it was a retcon. Meanwhile Kingdom Hearts planned major elements of the plot around the concept and set it up right from the start of the second game. If Miraculous had done the same kind of thing, then I doubt that most salters would be deeply upset by the concept. They still might dislike it, but it would be seen more as a matter of taste than as a true flaw.
*For those who don't know, Mycroft Holmes is Sherlock Holmes' older brother. Sherlock openly admits that Mycroft is the smarter and more observant of the two siblings. The same can be said of my sibling when it comes to story telling. Everything I can do, he can do just as well or even better. He's never seen miraculous, but knows the major plot beats from a mix of cultural osmosis and reading the occasional fanfic when an author he likes crosses fandoms. He is highly amused that no one he follows does anything save for fix-it type stuff and says it tells him everything he needs to know about canon's writing quality, an assessment I fully agree with.
