Women exhibiting this type of speech pattern have been made fun of for years; it's a big part of the "Valley Girl" stereotype. People think it makes the speaker sound uncertain and less competent. Again, studies have found that both men and women use uptalk; it's just that women seem to be far more criticized for it.
So, what's happening here? There's evidence that women are the ones who are the primary innovators in how our language changes. There are a few possible reasons for this, including their more extensive social networks or their role as the primary caregivers during infancy. But, no matter how young women develop new linguistic trends, they quickly and repeatedly run into the same obstacle: old white guys -- quite literally, in this case. Linguists actually have a term for them: Non-Mobile Older Rural Males, or NORMs.
Each wrinkle represents yet another YOLO-ing whippersnapper who won't quit twerking on his dadgum lawn.
NORMs hate change and are typically the last to adopt new manners of speaking. Linguists use them as a sort of linguistic time capsule, letting us know where the language was. The rest of us use them as a source for crotchety editorials, complaining about the way those danged-nabbit young women are ruining the language. But, this process is inevitable; our language has always changed. There's a reason we don't speak like Shakespeare anymore, and we apparently have young women to thank for it.