I get that opinion. But allow me to play the devil's advocate:

Mobile interfaces are small and restrictive. Touch screens and gestures have zero discoverability. Interfaces must scale to a multitude of different screen sizes and resolutions. Flare hurts usability in these situations. When designers break convention it is far more likely to result in confusion or frustration by end users. Well defined standards can enable me to use your app without even looking at the screen and drastically improve accessibility for things like screen readers.

I think the tendency toward flare stems from design education that emphasizes print media and tries to make a direct translation into Web/UX Design. Print media, and advertisements are meant to grab your attention, establish unique brand design language and brand identity. But If I'm already on your website or using your app you already have my attention. You've already sold me. Now simply help me accomplish the task I am here for in the least painful way possilbe. Branching out beyond common guidelines and creating new interface conventions may scratch your creative itch but it is rarely more efficient or easy to use that established conventions.