As artificial intelligence gets more and more advanced with the advent of machine learning and neural networks, consumer-facing AI like Cortana and Siri are facing an issue. That issue is the clash between an AI's subservient identity and the ethics behind giving an AI the illusion of gender. A large number of people end up denying their birth gender or eschewing the concept of a gender entirely, but the fact remains that gender is an issue in modern society. One of the biggest issues with gender is the traditional role and treatment of women, highlighted by the feminist movement. Most AI use a female voice and persona for an AI meant to obey somebody's every command, and it's not hard to see where the problem with that lies.
Google Assistant is one of the first AI to take steps toward fixing that issue, now that AI is approaching being sufficiently advanced to begin giving the illusion of an actual assistant. Such software is more capable, and more human, than ever. Meanwhile, Google Assistant, personality-wise, does not have a gender. It does have a past, and reportedly even has insecurities, making it appear human, but it eschews traditional gender roles when it comes to its personality. It does, of course, have a voice, which is female. The female voice was an asset that Google already had, having used it for Google Now, and at this time, there is no option for a male or androgynous voice. While some of the bots of media's days past, such as Robot Jones, may have sported machinelike, gender-free voices, this is not exactly aesthetically pleasing, leading to the widespread use of a female voice.
Calm-sounding voices in different varieties are available these days, and Google has said that they are looking into an option beyond the default female voice for Google Assistant. Should Google manage to completely de-gender Assistant, it could garner the kind of very public approval from the feminist and gender-conscious camps that the movement could spread. In this day and age, you can have your GPS speak to you as an everyman, a suave English lady, or even the dulcet vocals of Morgan Freeman, and Google is working to bring that same spectrum of choice to AI assistants.