Yes. Lets kill an almost ideal method of delivering an AI experience and replace it with a chat window. Because progress.
Yes I know Cortana wasn't successful but the reason it wasn't is because all it really could do reliably is tell you the time and set timers, tell you the weather and give you sport scores. Any time you tried doing any heavy lifting with it it would either spaz out spewing useless garbage, or throw up its hands and say "I don't know"
Here's a thought Microsoft. How about actually making Cortana like it's namesake and make it be inquisitive. Ask questions so it can learn what you want and how you speak for future conversations, or listen beyond the original phrase while it's talking so you can actually have a stream of consciousness type conversation with it instead of having to spend 30 seconds thinking up the exact 5 second phrase you have to say to it so it understands what you want. Also, These assistants never pass the "Jeff Goldblum" test. The minute you stop or say uhh or um or repeat a word in the middle of a conversation the assistant goes wild and starts talking gibberish while you incessantly order it to stop and invariably lose your train of thought.
To be fair, Google is no better with their assistant and from personal experience, it's getting much MUCH worse since they introduced it. Things that it would do easily no longer work the same or outright fail with the "Hmm. Something went wrong" message. The YouTube music rollout basically ruined the music experience with it to the point that your music library is held hostage and even companies and developers are abandoning their 3rd party actions on the platform. It wouldn't surprise me if the Google assistant ends up in the graveyard instead of doing something innovative with it and integrating their duplex and bard technology into the service and fixing the glaring user interface issues that people have been screaming about for the past two years now.
Amazon Alexa at least seems to be better 3rd party and response wise, but it appears Amazon is all but done with the service since it's a massive money losing venture. I don't see them integrating AI into it any time soon and I'm not even sure if they have anyone left on their development team that could do it if they wanted to.
As for Apple Siri. They're in the same boat as MS. At least hey have a good music service to fall back on unlike whatever the hell Microsoft had and it actually works unlike YouTube Music. Apple hasn't done anything innovative with it since they introduced it. That can of course change but is highly unlikely.