The Android Wear devices and the operating system has not been getting a lot of love from the company but it seems that Android Wear is going to get a new face and branding as there are hints that Google will be rebranding the OS.
This was first seen in the Android P Developer Preview as they refer Android Wear as Wear OS and replaced the watch icon with a “W”. This might not mean that they will change the name, but if they do it would probably be during the Google I/O conference in May. The reason for this is probably due to neutrality, same reason that Android Pay was rebranded to Google Pay which is because Android Pay could be used on Apple phones. There are some Android Wear devices that can be used with Apple as well so it would make sense to call them Wear OS, keeping it neutral across all devices.
These are all opinions on why the name change, but for the more solid reason we would have to wait for the official announcement of Android P during the Google I/O conference.