Nerd'ness aside (being one is a good thing... in moderation) -- choosing functionality over form if it's a mission/production critical part of your professional life is usually a wise decision.
For me, belt holsters don't work too well on sweats 😛 -- I work out of 'da home most of the time. That being said, I miss calls when the thing is stuffed inside my pocket. I'm no gun toting Cowboy, just a city slicker who can't reach it quick enough.
They'll never (well, never say never) fade into an arcane item of the past; but that's what has apparently become of the "Pocket Protector" (of which I absolutely love that photo above... Great movie! 🙂 )