Well Tom, you have your opinions and you are entitled to them, they can't really be called "wrong"
It's true that none of these fish are achieved in a natural way, but they vary from nature in different ways, and to me the methods is which they vary makes them acceptable or unacceptable.
Injecting them with an artificail dye that causes cancer in the fish is an abomination, and shouldn't be allowed. I bought some for my kids before I became better educated. Will never do again.
Crossing 2 fish that would not normally do so an achieveing a "blood parrot" is quesionable, and a fish I will not own. From what I have read, these fish are malformed, and some are unable to eat properly. IMO..also an abomination.
I am not familiar with the "glow in the dark" Zebras. If it's injected dye...you now know my opinion on that.
Now...I have just acquired some blue diamond discus. This is my first attempt at discus, and they were offered to me at a great price. I'm deriving from the dicsussion here that they must be selectively bred for the color, much as dogs are bred to fix "desired" traits. I was not aware of this when I got them.
IMO...selective breeding is different that the examples of the dyed fish and the parrots, but still not "natural.
Of course...natural would mean no stocking tanks with any captive bred fish, right? Does that include only using plants that are harvested from the wild?
A lot of fish and plants in the hobby are bred/raised in fellow hobbist's tanks. You will have selective breeding because the gene pool is limited in the "captive" envrionment. Breeding the same stock, and the offspring of that stock ends up with the same results as breeding a discus for a certain color..fixing the traits of that stock.
Just my thoughts....
Personally...I'm not driven enough to be that picky. My goal is healthy fish and a tank that is pleasing in appearance
"wild cows of Iowa"....ROFLOL...haven't met any up close eh?