The author of Fifty Shades of Grey, EL James, has signed three licensing deals to create themed clothes, a range of T-shirts, hoodies, tights, daywear, pyjamas, loungewear and underwear. The Telegraph noted that, as its central character Anastasia Steele spends most of her time naked, "we can't fathom what the range will be based on". This is because they haven't read the second and third volumes of the trilogy which, having moved on from the nuts and bolts of dominant-submissive sex, are basically shopping lists. Long, meandering passages of wish fulfillment – if you had a billionaire boyfriend, what would you want him to buy you next? There's so much Wi-Fi enabled Apple paraphernalia that at times it reads like an Apple catalogue written by a computer- generated sexbot. There are also large amounts of clothes, underwear, loungewear, office wear, everything your cut-out-and-keep everygirl might need for her sexual awakening.

There have been many criticisms of Fifty Shades: some were very droll ("a virgin without a gag reflex?" Suzanne Moore wondered); some I found a bit worthy (saying it's badly written is like moaning about the ingredients list on a Gregg's pasty); some I disagreed with (viz, that it glorified an abusive relationship – you can't legislate sexual fantasy, to make it conform to a worldview of perfect equality. Well, you can try, but it will just get weirder). However, this all concentrated on Fifty Shades of Grey, rather than Fifty Shades Darker or Fifty Shades Freed.

Darker and Freed offer a view of female sexuality that is much darker, yet more enslaving. It elides Steele's sexual identity with her consumer choices, while at the same time removing all those choices and giving them to her boyfriend (even her job, her pin money, is in his gift). Yet in the end it was irrelevant who held the purse strings because the subjugation that grated was not that of the woman by the man, but the way in which Steele's sexual appetites play understudy to her consumer appetites.

That's what the pornographic slavering was about – not sex, but diamond bracelets, jet skis, hosiery, purest silks, smart day-to-night dresses, Power Macs and 19-bedroomed houses with glass walls. In the orgy of self-adornment that was meant to characterise her sexual discovery, along with the torrent of outlandish gift-giving that supposedly betokened the adoration in which she was held, Steele fixated on the stuff. Her only moral quandary was whether or not it made her a whore, or a "kept-woman", to accept an expensive gift. What a tangential, trivial consideration, set against the travesty of letting your sex drive be all but erased by your consumer impulses.

Coincidentally, obituaries of Helen Gurley Brown, seminal editor of Cosmo, who died this week at the age of 90, mention, but out of respect, pass lightly over this issue: at what point does "making the best of yourself" cease to be about your own sexual fulfilment and become about buying stuff?

Gurley Brown occupied the rare position of being bete noire to both conservative and feminist opinion. In the first instance, it was down to her take on emancipation – that women should be sexually liberated and career-focused. In the second instance, it was down to her take on plastic surgery (she herself had breast implants at 73) and her insistence on female grooming and tweaking and perfecting. The world as she presented it had women constantly seeking to better their appearances in order to snag a better class of man. There is clearly a contradiction here: you can't argue that sisters are getting it for themselves if they then spend all they get on preening themselves for men. A truly emancipated woman, as she buffed and waxed and always tried to lose those last five pounds (Gurley Brown famously spent her life at 100 pounds, wishing she weighed 95), would say, "Hang on, who's preening himself for me?"

But in the end, this sticking point – "can emancipation and plastic surgery ever coexist" and the many attendant questions – did three things. First, it characterised feminists as people who deliberately wanted to make themselves unattractive the better to repel men, a slur from which the movement has only just recovered. Second, the message the mainstream took was that women were the victims of either surgery advocates (magazines), or plastic surgeons themselves, a view you can see clearly in this week's announcement that the government promises to "review" cosmetic surgery, for which read "rescue" women from plastic surgery cowboys. This narrative infantilises women, presenting them as peculiarly susceptible to self-doubt and dodgy sales techniques, which reinforces that image of needy, inadequate femininity that Gurley Brown – along with any given feminist – worked so tirelessly against.

More importantly, in my view, it obscured the real tragedy of this body-beautiful agenda, which is that narcissism, ever the advertiser's best friend, just spurs consumption. It might improve your ranking in the sexual marketplace, but it doesn't improve your sex life. Cosmo was and is criticised for inspiring women to hate themselves by pointing out all the features they could improve. I don't think that's always the case, but whether you tie yourself up in matching silks for reasons of self-love or self-hate, the result is self-consciousness, which is the enemy of sex. It's like taking crystal meth so you can concentrate on your PhD, then finding you no longer care about your PhD, all you care about is crystal meth.

This is why I shan't be buying Fifty Shades loungewear. Also, I am way too old, though Gurley Brown would probably give me a pep talk about that. It's for her pep, more than her relentless consumerism, that I hope she'll be remembered.

Twitter: @zoesqwilliams