Strelluf says that once people decide a linguistic feature has a sociolinguistic feature – that uptalk sounds indecisive, for instance – they then start to notice it more. It is textbook confirmation bias.
Deborah Cameron, a linguist at the University of Oxford, says: "It's definitely just prejudice, nothing to do with content. There is nothing wrong with the way young women's voices sound".
In her upcoming book Language, Sexism and Misogyny, Cameron writes that criticisms of uptalk almost exclusively focus on women, and that this can have damaging consequences. "Women can and do push back against this kind of criticism," she says, "but for every woman who gives it 'zero priority', there will be others who internalise the message that the way they speak is a problem, and that by not addressing it they are 'holding themselves back'."
Cameron ends her analysis of criticisms of uptalk and vocal fry by saying: "This is the paradox at the heart of advice telling women to speak with confidence: the more women are told that the way they speak is holding them back, the less confident they will feel."
Strelluf agrees that language judgements are usually personal. "Our evaluations of language are almost always really evaluations of people," he says. "For instance, we often say that French sounds 'romantic'. But there's nothing inherently romantic about French – half of French vowels are said in the nose, which should be decidedly unromantic."