Cortana's future is uncertain nowadays because Amazon and Microsoft are now working together on bringing Skype calling to the ever-increasing crowd of devices that feature Amazon Alexa support. According to Microsoft officials, Skype calling support will be available on Alexa-driven devices before the end of the year.
https://www.notebookcheck.net/Amazon-Alexa-devices-to-get-Skype-calling-later-this-year.333486.0.html