We crossed that line years ago. Windows development has just been layers of paint for years. Exchange has been on life support even though it underpins 365. The only Office updates have been style and icons (ok, and integration with OneDrive, but they still haven't implemented it for PowerPoint, shared editing still only works with word and excel). OneDrive is just SharePoint with a client app. Teams is also just SharePoint.

There are no software engineers at Microsoft any more.