I was asking because it seems like "platinum's" and other morphs would be farmed more commonly then they currently are, yet they have largely held their value unlike albino BN plecos or channel cats that can be bred consistently. I do agree that the "one in a billion" figure is referring to it appearing naturally.
Just some additional thoughts:
I guess it also comes down to selection of breeders in ponds. Once a morph has been discovered the farmer has the option to harvest it, sell it, or breed it some point In the future.
The farmer has an incentive to take the short run profit instead of waiting and breeding the animal for more profit at a later date but also incurring more risk. I see this often with my clients and their investments, they much prefer selling a position for a slight gain now instead of holding it and realizing an even bigger gain a year from now.
The breeding of recessive "morphs" (like piebald, long fin, and albinism) isn't successful in the F1 generation as the parental stock would only produce animals that look normal but are het for the morph. It would take breeding two of those f1 animals together to get 25% showing the morph in the f2 generation. If bred to the parent originator, it would only produce 50% showing the morph. It would take til the f3 generation to produce the morph with any consistency. Using Channel cats as an example, with three years to reach maturation, it would take a decade to produce morphs with any consistency.
Genetic Sexual determination can also play havoc with the paragraph above. If the founding animal is male and the morph is linked to the female genome of the species, it is unlikely to be passed on. In humans this is easily seen in the form of color blindness. As I do not know nearly enough about fish genetics, I cannot comment on this further.