I disagree...the killer app is a smart speaker (i.e. Amazon Music + voice control). That in an of itself is pretty useful, especially when you can get a reasonably good one for under a hundred bucks now.
Outside of that, Alexa isn't the platform the industry thinks it is but rather the equivalent of the touch screen on a smart phone. It's another form of input.
There needs to be much better and more seamless integration with 3rd party apps for it to really be useful.
You are right, I would say (Music + Voice Control) as you can configure other services (Spotify for instance), there are a lot of negative comments here, I wonder if it is not due to the population of Commenters on Hackernews that would tend to be younger.
If you have a child it is nearly a nanny that helps your child doing his/her homework, plus you can connect several Alexa (from friends) and interact with them, if you have also several Alexa you can communicate in different rooms (speaks/broadcast)
Outside of that, Alexa isn't the platform the industry thinks it is but rather the equivalent of the touch screen on a smart phone. It's another form of input.
There needs to be much better and more seamless integration with 3rd party apps for it to really be useful.