Could it be your own difficult experiences are colouring your view here Apples? I do not think Princess Diana was at her most beautiful during the period she was struggling with an eating disorder. At other times, she had an athletic yet feminine frame, which had aesthetic appeal.
In life, Diana’s attractiveness did not rest on being model-thin, nor on having features that corresponded to an impossible ideal. It is the slight deviations from perceived perfection in a face that give character, individuality, and, I would argue, authentic beauty to a real person.
To reiterate the point, being as thin as possible does not equal aesthetically pleasing! Compare the skeletal women in the Holocaust statue with the light and airy, voluptuous Three Graces. I wish something of what was captured in the latter example could have been present in Diana's statue.
(Slightly off topic but the subversive in me would love Banksy to steal into the sunken garden late at night and plonk a gigantic copy of his Princess Diana banknote right in front of the statue. That would show the establishment!)