Idk, I agree with the comment that said ML was raised (groomed) to be the way he is by his parents: someone who has no feelings and can only prioritize his family. He basically, quite literally, had no thoughts of his own until recently when the FL & Vivi started interacting with him in a way that he finds confusing/tickles his curiosity (what the story is showing us right now).
We can all argue that he could have broken free and he could have been old enough to think for himself the entire time, but honestly I think of Plato's cave (allegory of the cave) is a bit similar to him. We could tell ML to wake up and realize what he's doing is NOT normal, but he wouldn't believe us because that's what he knows as normal (that family comes first). That's basically ML the entire time, because he was conditioned that way. FL acting differently is helping ML, in a way, which is why he's different from the ML in the first timeline.
Just my opinion though ╮(￣▽￣)╭
I really dislike the ml I understand that from his perspective she was too much but still she was drowning if only he showed her security and affection I wouldn't hate him but how come he hated her in his pas life and now he care about her bcz she doesn't like him and changed??
Just for the record in the novel they cut her limb then paraded her with her limbs cut bcz they needed her power or something like they were to cruel i hate hem I hope this doesn't follow the novel