I would say nothing that iconic ever loses its value.
I will agree it feels like an abrupt development but yet I'm not unhappy about it.
As soon as they turned Galactus into the Life-Bringer, I knew it wasn't going to last. I know some people found it interesting but I thought it was a mistake to take such an iconic character and completely turn him on his head. That the story Ewing told was good in and of itself was fine but there's no way Galactus was going to stay in that form. And, in my opinion, he shouldn't have. I don't want Galactus as some good guy, spreading life throughout the universe, I want him to be the world devourer. There's no one else who can fill that slot. The MU needs Galactus to be Galactus and while I think they could've brought him back in a less clumsy fashion, I think the move overall was a correct one.