let me guess, trying to split away some of the power Redhat has by promoting Ubuntu.
Not a surprise but generally Microsoft just wants to be able to keep track of what their customers are doing. If some are migrating machines to Linux then they would rather they migrated in a way which allows them to track what is going on. A full on removal of Windows is what they have been willing to do illegal things to prevent. Probably some of the same going on here.