That’s a problem in itself, don’t you think? It’s all very “Feminists hate sex and they want to erase the differences between the genders”. Julia gets a taste of freedom and her right place in the world by putting on makeup and girly clothes and having a lot of sex.
It's been to long for me to be able to tell if that applies to the general context of Orwell's views (which apparently I'm not sufficiently aware of) or if it's also a significant issue with 1984. In principle having the woman character employ cargo cult femininity in a desperate attempt at self expression shouldn't be unsalvageabl. Being the only woman with a speaking part and also a ditz less so.
Winston being a self-aggrandizing tit who needs things explained to him a lot so the author can soapbox was the sum of my reaction to the character, that he was also supposed to be relatable beyond the basics of his clash with authoritarianship certainly puts a different spin on things.