There are many reasons why KP would be attractive to commercial growers, Shape, Color, Shelf Life, Good taste.
But I think that maybe one of the reasons its preferred by so many in Australia is because its what people have grew up on. to consumers, the KP is what a mango should taste like to them. other varieties may be considered too sweet, too small, not colorful, Insipid, too strong, because they are comparing them to KP.
Many articles have been written on this subject, Its hard to introduce new fruits into a country that is not familiar with them, it takes decades to get new fruits to become popular. its also difficult to introduce new varieties of fruits to people that have grown up with something they already love.
I have not tried a KP yet, I would love to have one, and would even like to get a tree someday, I wouldn't be surprised that my climate and soil will give them a different flavor than those in Florida .
This whole situation reminds me of the Alphonso, which has been billed as the best mango in the world by many, yet from comments of those in Fla that have tried them, its just a so so mango. how can this be? is the Alphonso to blame? peoples preference in taste? climate? soil? national pride?.