I assume you’re referring to our tribute post to the inventor of Kevlar, Stephanie Kwolek, but no – I don’t think Kevlar vests are inherently biased against women. Certainly no more than chainmail.
It doesn’t matter what kind of armor you intend to wear – the better fitted it is to you the better it will protect you and the more efficient you will be in it.
The only way it won’t apply is if you happen to have the exact same measurements at the mannequin used in production (which doesn’t apply in the cases of things like field plate – which are always custom made). As with so many things in life, being rich is a definite advantage when it comes to armor of any sort or time period.
Guidelines for police and other parties that regularly use bullet vests recommend that the wearer not change their body mass by more than ten percent after being fitted for their vest. That means bulking up, no slimming down or putting on fat.
Many women are quite comfortable wearing even covert Kevlar armor intended for men because it just happens to fit comfortably. Many men cannot fit comfortably into a standard vest because they are not “standard” shape and size (I’m one of them).
The only difference with “female” vests is allowing space for breasts, primarily for covert body armor (that is either concealed under clothes, make to look street clothes or easily concealed with a jacket). While there is less variety in stores entry level concealed vests for women cost the same as entry level concealed vests for men.
And again, the actual reason for different shaped armor here is not about effectiveness of stopping bullets but rather about comfort while maintaining a silhouette in order to conceal the presence of the armor -by making the wearer meet society’s expectations and fit into their regular clothes.
Actual military grade armor is not just Kevlar, but also additional features such as ceramic plates. That’s why you won’t see any boob bulges on the anti-ballistic armor worn by real female soldiers (who wear the same tactical vests as the male soldiers).
Needless to say that the people who train for very specific tasks and tend to have low amounts of body fat (and so are unlikely to be busty).
There is really no reason to think of Kevlar as an inherently problematic armor for women. There’s nothing special about the way if functions, it’s simply an awesome material for making fabric for armor out of and has been the core of modern anti-ballistic armor for decades.
Like every armor of every era, modern armor is designed around the expectations of the market – as women are becoming a larger part of that market, it is adjusting accordingly.