I asked this very question a couple of weeks ago and it appears no one has come up with a solution for the newer bikes. I think we are stuck with what we have unless you are blessed with the gift of "modification"
I have researched this question "to death" since I got my 2016 MTS1200S in April.
The sad truth is there is NO ONE that is making a "Tidy Tail" for the 2015 + bikes. Ducati ( in their infinite wisdom ) made the whole tail assembly a complex nightmare. What is needed is a new "molding" that replaces the entire lower piece (, eliminates the turn signal mounting but incorporates the Tail Light mounting and License plate holder.