...in all fairness, she IS an eight-year old in both mind and body, and not a reincarnator or returner nor any other version of an old person in a young body.
Makes sense that a ghost, who's probably somewhat older or more knowledgeable, would know better how to go about things.
It just feels so weird with how most manhwa tried to justify our wordly protagonist...but even then, she's just slightly mature instead of actually mature. Nice to have this bucket dropped this early, to better temper expectations.