I think you have missed the point.
Edward was supposed to be King after George V. Edward ran from his duty and abdicated.
Making her Father King, the stress of being King killed her Father.
Edward should have had kids, but did not.
Elizabeth being Queen was not a certainty because Edward should have been King, had children and done his duty.
Also, yes Elizabeth COULD have been Queen but not be in line as a child and Queen at just 25 because the burden of being King killed him. Yes she could have been Queen but her childhood would not have been over at a little child and her family not the carefree happy family it was because of the burden of the throne.
Please go back and re read and see the problems that had nothing to do with her being in line but because Edward abdicated and when he did
Also she didn’t hate Edward! Wallis was always seen as the real issue by the family. Elizabeth met Edward several times before he died, she was very eager for her children to meet him. Queen Mary tried for years to get Queen Elizabeth the Queen mother to meet Edward with Elizabeth and Margaret. She pleaded with her to let the old battle end.
It boils down to Edward not facing up to his responsibilities and being led astray by undesirable women. Whatever the truth of the relationship between Edward and Wallis it is well documented how much control she had over him.