We have tons of questions about how to get "optimized for iPhone 6 and iPhone 6 Plus" label for your app in the app store. But now I see that none of apps familiar to me (mine and even facebook) display the label anymore. So has it been removed nowadays? Or do I have an issue?
It appears to have been removed.
Earlier, you could add it by adding either a launch storyboard or launch images — which you should still do. (See this question.)