Well, there are upsides. If you could completely genetically engineer animals for the pet trade, you may relieve some of the stress on the natural environment by relieving some of the harvesting for pets. And I do like some of the fish. I have never seen those parrot fish. I just don't think some of the companies put enough thought into this before selling them. What if there is a side effect of one of these genetically altered danios being susceptible to a bacteria that they are immune to in their natural environment. Then some of them get into the natural population, breed, and the whole population slowly dies off before the introduced fish fall prey to it. Just one of a million things that could go wrong that nobody has tested yet. For an example, see: Africanized honey bee
