What you call "tattered", I call "fringed"

As the fish gets older, the pecs adapt this look, even in the most gentle, kindest environment. I kinda liked fringed jackets when they were popular, too. Perhaps Yanks are more accepting of the butterfly because we're basically more open to diversity, to the "unusual", and see the beauty in the animal for what it's worth - not expecting it to conform to someone else's pigeon-holed definition.
I have both: a smallish pond for the butterflies (and shortfins if they need a gentle place to recoup), and a larger pond for the "koi". My husband refers to the butterflies as the "good fish" - in his photographer's eye, they're more graceful, serene and elegant in the water. Koi are more massive, stronger, fighters (salmon in a pretty coat!).
It is a matter of opinion and taste, pure and simple.
Lee