here comes my (bit late) answer but I've been doing some research and plus work kept me busy
I agree with bed that the slogan of Google "don't be evil" is not applicable anymore nowadays. The tech companies mentioned by bed playing in the same league.
As Joplin put quite a focus on privacy you have to explain in detail (not just linking to their statements, as press reports could tell you the opposite). I'm quite sure that there conversation out there giving us some more insight. I would like to see some research ongoing before we going to include any of their AI.
DialogFlow (now Google) is not the only machine learning library discussed here, e.g. TensorFlow (Google) but OpenSource and listed top at FOSSPost.org.
There is even a new kid on the block Open-Sourcing Metaflow, a Human-Centric Framework for Data Science what shall extend others AI instead of replacing.
That get me to the question of how easily can one AI replaced by another one. A recent example where this was necessary is home-assistant.io, what I follow closely. There was great integration for Snips Voice Platform but that was closed after the take over by Sonos. Luckily they came up with Almond & Ada: privacy-focused voice assistant.
So you see, many thoughts which are seeking for answers 
Moreover, AI was also discussed in other topics, so it would be great if the AI^s job could be extended to cover these ideas (at alter stage), see
...
Last but not least my sources
https://fosspost.org/alternative-software/developers/open-source-ai-machine-learning