We never got an answer about this. I've gotten SO MANY Neo Bubble fails in the last month, it's not even funny. With the space and food limitations, I seriously doubt anyone wants habitats full of Neo Bubbles. And it's not the only new dragon that isn't tradable- most of the new ones are not.
The measly 100-coin sell rate for all dragons, regardless of rarity, was tolerable in years past because you could trade the fails off instead of taking a total loss (yes, 100 coins counts as a total loss). Gems and lotus blossoms are a nice thing for lower level players who are working on the crafted dragons. For the higher level players, there may not be much to do with the gems, but at least it was *something* to show for your endless hours of failed breeding efforts. Getting repeats of the new, untradable dragons is just painful. It feels like banging your head against a brick wall. Each and every 100-coin Neo Bubble fail wastes 20 hours of time.
I don't see WHY the change was made? It makes no sense. The small number of items players get for trading dragons (gems, lotus blossoms, the occasional scroll) doesn't effect your bottom line, at all. There is no way for S8 to profit off of removing the trade option.
Every single player spends the majority of their time in this game dealing with fails and repeat, unwanted dragons, especially the common ones. Removing the ability to trade these dragons is not only disheartening, it lowers the quality of the game.
Please make dragons tradable again.