I blame her grandfather... spare the spinach, spoil the child.
Fixing her spoilt personality would be a factor if she was the old Britney. Technically, she is a different person, so fixing her personality became.. uh nullified? The new soul was kinder, so no point in trying to change if she already changed (I guess :/). Tho, this is a wasted opportunity for development id say; that kind of story would've been interesting as well since ppl don't approve of the fat shaming aspect.
From what I see, the new soul seems to be obsessed? (or at least heavily conscious?) about her own appearance that she even knows the production and ingredients of beauty products (tbh I don't remember, I think it was stated that this was her past hobby, right? idk. The main point is, she cares about her appearance a lot). Knowing this, when she gets transported inside Britney's body, I guess u could say that it became a nightmare for her past self? So now, all her focus went towards fixing and maintaining her appearance :/ which is uh interesting, but feels tedious
While I do get why he would feel annoyed of her, it sort of feels off putting that what’s been mentioned on and on again is about her weight. Shouldn’t the main problem have been her spoilt and uncontrollable personality?