I don't know a single person using Cortana, so it's not a surprise I guess. At least the push to use it in Windows will finally go away... A bit too late I have migrated to Ubuntu earlier this year... Puting an end to 20 years of Windows on my computer. Farewell Microsoft.
Does anyone use any voice assistant anywhere? Other than people trying it out for the first time, I've literally never seen it in the wild.
I really can't make myself talk to a machine. I even abhor the phone answering services that insist that I speak instead of punching numbers. I my household the only person that interacts with the Echo/Alexa is our 3 year-old daughter. She finds it funny.
On the other hand, the voice assistant devices are selling like crazy, so people are interested in them.