A couple of days ago, Microsoft backed off adding Cortana integration to Dynamics 365 There was no definitive reason as to why this was occurring, and the company even noted: "we welcome your feedback and ideas." Today the saga has developed a bit more, and Microsoft is now hinting at a more open integration in the future (via Neowin.)
The same blog post about Cortana integration with Dynamics 365 now headlines: "Work continues on Dynamics 365 digital assistant experiences." Though not mentioned specifically, this does hints that Microsoft may be working to bring Alexa and Cortana together in Dynamics 365. See the statement for yourself below.
We are working to deliver a robust and scalable digital assistant experience across all of our Dynamics 365 offerings. This includes natural language integration for customers and partners across multiple channels including Cortana. To that end, we are discontinuing the current Cortana integration preview feature that was made available for Dynamics 365 and we are focusing on building a new long term intelligent solution experience, which will include Cortana digital assistant integration.
As you may recall, Microsoft previously detailed they would be working with Amazon to integrate Cortana with Alexa. The two companies missed the deadline, but Microsoft recently insisted that the two are still working on the integration. With this so, Dynamics 365 somehow could now be involved in the Cortana and Alexa partnership, especially because of the "long-term intelligent solution experience." and "partners" phrasing.
Again, just speculating, as Microsoft has not said anything beyond the new statement seen in the blog post. It also could be the way of the company being more open to the competition, and allowing digital assistant integration to all, but there's no telling, especially with the news that Amazon Alexa would be coming to some Windows 10 PCs.