Of all the things that could be handy regarding an Apple Watch on the 3D Touch menu... pairing a new watch, is something most people only will be doing every other year. Why have THAT as a shortcut? Why not 'Change watch face', or 'Ping Watch'... or 'Open Notifications Settings'
That's just off the top of my head as some things that would be WAY more useful as a shortcut.
That's just off the top of my head as some things that would be WAY more useful as a shortcut.