Wow

I get what you're saying but she's not "isekaid" in the stereotypical sense. What she identifies as isn't her previous "Earth life," there are parts where you can tell that she just vaguely remembers the feelings of it, like a dream. Her identity is Athanasia, and Athanasia is still child. She's fully integrated in the world she lives in and she's being written so that her identity and personality is because of it.There's no extra Deus Ex Machina knowledge or personality that ties her to Earth or her past life that makes her identify as someone older or more informed any more than the memories of the 'original story'. It was just a troupe used in the beginning of the story to make her a more reliable narrator and explain her early conscious. She quickly ditches that because she lives in that world and is developing according to how she's being raised and her surroundings. Aside from being mentally cognizant as a baby she's grown at the same rate as everyone else and has always been true to her personality.
So I suppose that even if she remembered living in Earth and those hardships, they slowly became less and less her identity because the world she lives in is just as real to her as Earth. In other Isekai novels they tend to treat the 'new' world they live in as the "other" because in part that's the bad writing of the author just implementing themselves in the world they wrote, and also because it's easy to just apply Earth comparisons to the reader to skip some aspects of world building or for easier understanding by analogies.

AHH thanks for explaining it and taking your time to write all of this I understand it now much better thanks!