You mean your phone that has its own built-in, unswappable assistant? Since Windows Phone died[0], I can't blame them for getting out of a business where they are immediately outleveraged by the competition.

[0] I say this with lament, because it was IMO a legitimately good phone OS. My Lumia 920 is still my backup phone, 8 years later, because the ones I got after that died before replacement. But the death was certainly not a surprise. Once they started adding more features to Android apps than existed in the Windows Phone versions, the writing was on the wall about where the money was going.

They're adding it to the Teams and Outlook apps and pushing Cortana toward businesses.