I'm going to give some of our situation. My mother is functionally a quadriplegic with MS. She has about a foot range of motion in one arm and two fingers that she can make work sometimes. The Echo solves or will solve a lot of problems for her. It is relatively inexpensive, built to take advantage of other devices, and isn't way behind the tech curve like most medical devices. Having a device she doesn't need to touch and can hear over the tv is huge for her.
This may blow your mind, but my mother hadn't even turned off a light switch for about 9 years. She can't get to the thing she'd want to use, she frequently can't reach for the device, and she then can't make her fingers work to manipulate it.
I've seen some posts putting down the reliability for something like 911, but that's because you are able bodied. There are millions of people who have a hard time moving around. That's bad enough. Then there are people like my mother where an 80% success rate would be life changing.