I spent some time at Christmas setting up and exploring Amazon's Echo for my mother-in-law. It was a gift from her boyfriend, and the idea was that it would be an able assistant as her MS continues to progress.
We enjoyed playing music, setting up shopping lists, and having Alexa tell jokes. But beyond that, it was tough for an older person to find much utility to justify the price and learning curve.
However, I do not think that older people (defined as over 25!) are the target audience. I think that children are. Just like babies swiping iPads in 2010, we are starting to see kids that are growing up in a voice controlled world before they learn a keyboard or phone. In a recent article by Ben Thompson (subscription required), he shared reasons his household has embraced the Echo:
The degree to which my kids love interacting with virtual assistants (not just Alexa but also Google Assistant and Siri) is startling. They are constantly figuring out what each assistant can or cannot answer, and don't get frustrated at all when it doesn't work; it is very difficult for me to imagine them living in a world where voice is not the dominant interaction interface.
Why learn about apps and websites when you can just ask verbally? This idea should make anyone involved in UI/UX design think about the future of their career. Or maybe UX shifts from screen experiences to voice experiences? We will find out in the next five years.
More perspectives on voice assistants:
Fred Wilson (VC) - http://avc.com/2017/01/a-side-by-side-comparison/
Tom Harrison (developer) - https://chatbotslife.com/amazons-alexa-echo-changes-everything-12ba621ea6ce#.trvq034pv
This clip from Star Trek 3 is a great perspective!