I am still learning about the recent API release out of Apple, and working to keep up with the volume of resources coming out of the Amazon Alexa ecosystem. However, two things that I know for sure are that Amazon is way ahead of the game and that Apple will have to invest a lot more of their resources if they expect themselves to be able to catch up. Apple may have the device advantage, but Amazon is leaps and bounds ahead when it comes to how to develop a community in support of voice-driven applications.
In fact, I would not be surprised if Apple's release was actually in response to the waves that Amazon is making with their voice platform. When it comes to the platform battles between tech giants, companies are able to throw the necessary resources at things to play catch up—but it is something that other, more small players will not be able to always navigate. I am reviewing a number of device-focused API efforts lately and the ones who launched with an API always seem to be ahead of the game.
Learning to do APIs well takes time, and learning to grow your API community of developers and partners will always take time to do properly; you just can't throw resources at it in order to make things scale properly. Thus, you might as well kick things off with an API and platform approach even if it is in beta and limited, because at least you are getting going in a limited environment. Siri has been out there for a while now, but not as a platform—and I'm going to wager that this will be a significant handicap.
What is your approach to technology? Do you think it is more like Siri or that it is more like Alexa?