Last time I checked even a shitty smartphone can access YouTube, a service far more appropriate for gameplay clips. Just because .webm is widely supported doesn't mean one should continue to use .gifs badly.Gifs have still got a use until webms work on mobiles.
Seriously, I hate massive 138980MB gameplay gifs and GAF is awful for them. I'd even prefer to consume tumblr gifs non stop for the rest of my life.