Somehow they all use she/her pronouns or a feminine voice. I don’t have a firm conclusion on this yet - I just think this is a very odd trend. 

Will be added to as I find more or as people suggest more.

Cortana, from Microsoft. Source: https://www.washingtonpost.com/news/the-switch/wp/2016/04/07/why-poets-are-flocking-to-silicon-valley/?utm_source=nextdraft&utm_medium=email

Ava, from Ex Machina. Source: http://www.wired.com/2015/04/ex-machina-turing-bechdel-test/

Siri, from Apple. Although I guess it’s more her than her creators? Unclear. Source: http://qz.com/409787/7-times-siri-understood-gender-identity-better-than-most-humans/