Xmas gifting

My four year old daughter has asked for a Barbie doll for one of her Xmas gifts this year. Perfectly normal request for a 4 year old girl. I had similar dolls when I was younger. I can afford to buy it for her. That said I am reluctant to buy it for various reasons but mainly because I want my daughter to grow up with a positive body image and I believe that Barbie dolls and the like promote quite the opposite and a totally unrealistic version of what a normal woman looks like. I can obviously choose not to buy it for my daughter but then have the thought she will be disappointed and is not of an age where she would understand why I did not buy it for her. It seems unfair to her somehow to impose my adult values on her as a small child who just wants a toy doll to play with. I don’t know how to reconcile these two thoughts.