Half the family have just had nervous breakdowns trying to figure it out! No better on Android than iOS, though the Mac App is clearer.
It seems as if the Roon guys don‘t like playlists at all. Creating them is one thing but if you one day are going to edit them… Have fun! Especiallly if you added streaming titles to your list. You can delete them one by one with lots of clicks each. For me playlists are the natural way to organize my stuff. Obviously most users go other ways. Or maybe they just browse through a huge catalog of files. I don‘t know.