What does this have to do with classifying them as a success or failure?
But while we're on your topic, don't forget there is value in brand recognition and trust in a company which isn't a random Chinese vendor. And why do you think the Chinese clones exist at all? They followed the success of GoPro.
For enough people a premium iphone is worth the wait xtra cost, which is why Apples smartphone profits are greater than all other smartphone makers combined.
The sensors & lenses are going to be the same size, from sony and rubber gaskets with a hard plastic shell is not hard to do.